Hey folks, well I thought I'd throw my two-penneth into the mix of ideasfor ME3/moans about ME2. I know some of these things have been said before (if not all of them), but I've only really read the first 5 pages and the last 3 pages, but I thought if we say things often enough and loud enough, then hopefully Bioware will take note of the most popular things and incorporate them before they get too deeply into the development cycle for ME3.
N.B: These opinions/suggestions are based on playing KOTOR2, ME1, ME2, and some of DA:O (I've put it aside for the moment - I'm RPG-ed out...), as well as designing my own near-future ARPG (Action RPG) based on the Bioware style.
N.B.2: These opinions/suggestions are alterations I'd make to a good ME2 to make a fantastic ME3.
N.B.3: If you don't want to read the following essay, then flick to the summary at the bottom.
1. Squad Armour Customisation: I liked the ME1 approach of being able to change out your squad's armour for something better. In ME2, if I took Miranda to a hostile planet, she still wore the same white jumpsuit that she had on-ship, but with a little clear respirator (sp?) thing. She might be designed to be superior, but even she needs a good combat suit on to land in these places.

Could we have back the ability to swap out their armour?
Incorporate it into the same system as we use to change Shepard's appearance in ME2, and it's a real winner; e.g. Allow us to purchase bespoke pieces of armour (such as the Capacitor chestplate/off-hand ammo pack), which can be pooled like the human armours were in ME1, and also have a series of upgrade projects (better shields, higher health, etc.) in the ship's lab.
2. Conversations: Can I speak to my team/NPCs more before things get onto a circular path? I was kinda disappointed that although there were more options than ME1, the chat tended to die off fairly quickly. And, if they're busy, let us know before we engage them in chat! I got bored of running around the ship trying to speak to folk only for them to tell me they were doing something and could I come back later... Repeatedly.
Also, can the conversations/background action at the big locations (i.e. Illium, Omega, Citadel) change a bit every now and then? I'd like to come back to Omega after a week or something and find a different set of folk standing in the queue, etc...
3. Squad & Shepard Stats points: Can we have more of these please? And more options to spend them on? I like having a tighter number of skills, but it was possibly pared too close to the bone. I did like having fewer things to spend points on, but I'd have preferred to take more points and spend them on a wider range of things, making my combat squads a bit more flexible.
So, whilst my Adept can now throw folk around, Warp their armour/shields, and whatever, I'd like to also be able to chuck a couple of points into his bartering ability, making my paragon/renegade status not as crucial for dealing with merchants. Or I could put them in his weapons-handling ability, giving him faster reload times, or higher accuracy, or something. This is obviously in addition to having his usual Biotic skills. Differing options could be presented for the NPCs in the squad too, maybe even a couple that are useful for non-combat environments and missions!
4. More Mordin: He NEEDS to be in the next one. Fantastic character. The "Scientist Salarian" was hilarious, as was the dodgy William Shatner-esque speech pattern.

And his powers weren't too bad, though I would have liked a ranged one (like AI hacking or a poison gas grenade). I brought him along because his asides during the exploration and the cutscenes were priceless. He could be described as the comic relief, but that's why he was so good, as it stopped the game from getting too po-faced and dramatically overwrought. A character I actually cared about, particularly during his Loyalty mission (fantastic voice-acting and animation).
5. Paragon/Renegade/Morality/Shopping: Could the discounts & options for getting a discount be separated from our Paragon/Renegade scores? Not completely, because a bad-ass skull-****** or a paladin of justice will obviously be more skilled at talking a merchant into something, but have a grey every(wo)man Shepard capable of sweet-talking them into giving him/her some sort of discount based on, say, a Barter skill you can chuck squad points at.
Also, despite their differing personalities, my squad members followed me around like faithful puppies no matter how good/bad I was. I'd like a sliding scale of individual approval/disapproval from the squad members, the rest of the crew (group approval/disapproval), and maybe the rest of the game world, much as we have in DA:O.
6. Upgrades: I did like upgrading things better in ME2 than buying/looting the upgraded stuff in ME1. After all, there weren't a 1001 things I had to convert to omni-gel or sell to someone. I like the new weapons, but I'd like to be able to improve individual weapons.
For example; have 2 assault rifles, the M8 and the M15, but have differing stats, so that I do have to choose between them, such as the M8 having a larger magazine, but less punch at range. The M15 has a heavier punch, but isn't as accurate in automatic fire. Further to this, allow me to upgrade the M8 with a longer barrel, or better optics, but also allow me to get recoil compensators for my M15. Or something.
The same could be applied to heavy weapons. They all had a reasonably generic description at the top of their page, but I'd like to know info such as "+40 against shields, splash damage 5 metres", without having to resort to looking at the Mass Effect fan wiki.
7. The SSV2 crew: The space hamster! But seriously, wandering about and hearing other crew members talk was great, as was walking up to the cockpit to speak to Joker & EDI after every main mission, just to hear what pithy response you'd get. And Kelly was great to chat to/flirt with. However, it did feel somewhat sparsely populated. I know she's only a wee lady, but surely the old girl's got more than about 15 folk aboard (not including your team)? And could I chat to more of my crew please?
8. Planet-scanning/Resources/planetary landing: Planet-scanning was, in a word; tedious! Better than finding random minerals when you flailed about in the Mako, as you actually NEEDED to find these resources, but so dull to play. The only high-point was tracking the height of the peaks when you got close to a mineral deposit to get the maximum amount of resources.
So, how about this as an alternative: you do the first 'ping' of a planet and from this EDI points you in the direction of where you might find interesting things, like large resource deposits, or local settlements, in an area that's got more alien flora and fauna. You scan close to it (as you would by tracking the height of the resource peaks - EDI's directions should be vague, not a white blip like you get on an anomoly), and launch a probe, that leads you to either automatically gather resources, or randomly be able to land.
Seeing a herd of lumbering space elephant-analogues move across a plain of tall alien grass/plants whilst standing next to a massive deposit of Platinum she pointed you towards would be a satisfying conclusion to a small-scale exploration mission. This could also satisfy the idea of doing more missions on planets (and not necessarily combat/N7-type missions), which is something I want to do.
On the resources note... If I've done all of the upgrading, but I still have a shed-load of resources that are now essentially useless, why can't I sell them to someone? It'd be a nice way to get extra cash, and you won't feel like you've wasted the extra time gathering the resources in the first instance. If you wanted to get complex, you could have the market value of each resource changing regularly to reflect something happening within the game space (e.g. Blue Suns capture Eezo facility, the price of Eezo in Council space goes up. Alliance fleet announces fleet expansion, price of Palladium goes up in Human territory, etc.).
9. N7 missions/Hammerhead: can we have the Hammerhead as a bigger thing in ME3? It was like the Mako, but good! To be fair, the DLC missions for the Hammerhead are a bit confusing at times, particularly with new and improved "Screen-shake-ovision", but a lot sounder than the Mako sequences from ME1, which tended to do nothing other than bore me into a coma.
And the N7 missions were a LOT better than the Mako, which handled like a drunk cow on rollarskates. Most of ME1's missions on planets tended to be about bouncing about the place until you found the interesting location and had a bit of a bust-up/chat with the locals (who all tend to wear the same get up, even in ME2). The N7 action missions tended to bypass the drudgery of wandering about doing bugger all, whilst the Hammerhead stuff was nice and tight, and always had fun jumps to do.
10. The shooter/combat side of things: Don't change it at all! The balance is perfect. The locational damage model felt substantially better than ME1's "throw a ton of rounds at the buggers until the invisible HP counter reaches 0 and they cark it" (and the YMIR Mech's nuke-like head shot death in particular was wonderfully pleasing). I Liked that you didn't automatically take cover. Also liked unlocking the Assault Rifle, as it made things slightly more realistic, as, after all, your Shepard's supposed to be a former Alliance soldier (even if he is a Biotic/Tech specialist), and most soldiers use an assault rifle in my experience (even officers!).
The biotics are sooo much better than ME1. A bit annoying that because Blue Suns Goon #1 had decided to put on his armoured codpiece I couldn't blast him with a Throw, but there's ups and downs to everything.

Remember folks, at the start of ME2, the Biotic powers were still fairly weak (I changed class from my imported Vanguard to an Adept because I wanted to throw people around the map, not run at them with a biotic charge), but as you ranked up they definitely improved, particularly as the game progressed. Would have like some sort of area effect "get away from me" power to stop getting overwhelmed by bloody Husks though.
On that side note, less of the gorram Husks! Bullet sponges every man jack of them. I'm glad I went as a Biotic, because I could just Shockwave them all as they ran towards me and they'd pretty much die. As soon as they got close to my Shepard, it pretty much ended in death (for me at least). Or give me a defensive "get away from me" thing, dependent on class, e.g. a biotic 'Blast', or a tech-based area Overload to stun the buggers whilst I legged it to somewhere where I could kill them safely. The soldier could drop an EMP grenade or something...
11. The endgame/big climax: A couple of bigger missions like... Hmm... How to explain this without spoilers... The big end-game mission against the Collectors! It was a blast when I played it! No swapping of squad members once you'd chosen them, make decisions pretty much on the fly, no mid-mission Saves (other than auto-saves). Fantastic! So much more intense than the final mission sequence on the Citadel in ME1. I genuinely dithered about who to assign to what role at various points, as I didn't want anyone to die (feeds into the new characters bit). The lack of mid-saves is, I think, what did it, and the epic length of it (I had to sit through it in a single sitting from the moment I went through the Omega 4 Relay until the credits rolled).
Could we have a couple like that in the next game? And maybe something to do post-credits that's fed from your success/failure in the the Endgame? Coming out the other side of the big mission, it felt somewhat of a let down to just be back to resource-gathering and some N7 missions when you'd just saved Humanity.
12. The hacking/bypassing mini-games: They were fantastic. Certainly more realistic than getting the immersion breaking "sorry, your squad's not intelligent enough to hack this" message that you got in ME1. And actually fun to do, compared to scanning. Keep them too!
Hmm... A bit of a longer rant than I anticipated, but I hope it was constructive to people, and hopefully Bioware...
To summarise (for those of you who couldn't be bothered reading the full thing and shouted "Skip to the end!" at the monitor

):
More squad customisation, more conversations, more N7-style exploration, more points to spend, more options to spend them on, more and varied upgrading (make us choose which weapon to take), a sliding morality/approval scale distinct from selling/buying options, less planet-scanning, less Husks, keep the hacking/bypassing mini-games, more news reports/background action, nice locational damage model, more epic length story missions where your decisions matter (think endgame of ME2), let us sell minerals and stuff we don't want/need, more Mordin!
Thanks for your time,
Tim