There may be ME1&2 spoilers regarding things I hope improve somewhat in ME3, in case that needs saying.
My major beef with ME2 is how the Paragon/Renegade options, while done better than in any other game I've played, make you feel rewarded only if you're heavily invested in one or the other. In particular, the final persuasion while at Morinth's apartment, as well as making up with Jack or Miranda after siding with the other, feel like options I know are coming (on re-playthrough) and don't want to miss. This makes me play either too nice or too mean when I am more like 2/3 and 1/3 at heart. Sometimes I just wanna tell Jack off, or say how what Jacob's father did was tempting.
I've wondered if they've considered making a 3rd path where you are occasionally rewarded for making more "logical" choices. Consider Jolee Bindo from Knights of the Old Republic. I never visited the forums enough, having only played most of the recent Bioware hits, plus KotoR in the last few months, to know whether or not he was a popular character. I suspect he is though, and if there's one thing I've noticed, Jolee isn't calibrating the 3rd time I talk to him. As many of you may recall, he had a seemingly unending amount of things to say.
But that's all amiss from my original point, that he was, at least according to his character page, neither light nor dark side (ultimately, he was more light because of how the story plays out, but still). And in spite of his ultimate light side leanings, his more neutral, logical view was extremely refreshing, and not just because he was a Jedi and wasn't spouting the usual crap. "Pragmatic" is probably the best way to describe him (after "testy," anyways), or at least his worldview. That doesn't necessarily translate into "out for himself," because he's neutral, but rather he prefers a simpler life where he's willing to help people if opportunity arises (e.g., wookies) than to go around being self-righteous and potentially causing lots of severe unintended consequences. That doesn't mean he's like Tom Bombadil or something; neither of them are immune to the dangerous world eventually crashing around them--the possible consequences of inaction, etc.
So my question is: is there some reward, a path along the lines of a pragmatist, like Jolee Bindo? And I personally am still, as I said, about 2:1 Paragon/Renegade, but a path like that in ME2 will miss out on some later persuasions, with nothing gained other than the seeing a few lines you wouldn't otherwise. Those lines are available to Paragon/Renegade anyways, if the choose to ignore their available persausions. Will I feel anything gained for choosing a middling alignment path? Aside from the different lines of dialogue, which I would enjoy sooner or later on other playthroughs, there is no late game investment for avoiding extreme Paragon/Renegade alignment. There's only the inability to persuade
I'm not suggesting some huge reward where if you balanced your Para/Rene scores as evenly as possible, a purple or black conversation option opens at some critical point late in the game. I just don't like the feeling that the traditional blue/red persuasions are necessary or else I'm missing out, which somewhat pigeonholes me into a path during the whole game.
I've considered ignoring persuasion options, but for whatever reason, I feel like I'm letting Shepard, and her companions down if I click on whites while blues/reds will only appear once. In short, it feels like "settling"--settling for second best.
If there was such a path, I can still see why its overall use should be less in scope than the more natural progression of Paragon/Renegade. Those are investments and the persuasions associated make sense to be available, whereas it would be much trickier to balance the amount of reward/investment for a "middle" Shepard. It could easily be "too good" compared to the traditional alignments. Sometimes the more "logical" choice that makes you scream with dramatic irony "why didn't they just fly eagles over Mount Doom and throw in the Ring!" won't serve the story very well. However, it would have really been handy to, for instance, freaking explain the situation to whomever you meet at the end of Horizon (Kaiden or Ashley)--not that that was ever gonna happen, and honestly alignment wouldn't have really mattered anyway, but I think you get the idea.
Additionally, I really hope that persuasion options as far as talents or whatever aren't tied to a 70% or 100% talent. Playing as commando instead of shock trooper really stresses that aforementioned pigeonholing. I'm with Shale on anything related to pigeons.