Well, I can't really make a list for DA:O as, to my mind it was (with some very minor exceptions) a 'perfect' game - one of the very few truly perfect games I have encountered. I really cannot praise it highly enough, no other game I have played has affected me so deeply at an emotional level, or immersed me so completely within the story and environment.
If I were to be picky, I'd say that the Runecrafting system in Awakening was a bit clunky.
... Also I yearned to have some opportunity to explore the world a bit more freely, actually travelling overland to some locations. Ok, it's not really designed to be that kind of game... but I often fantasise about a Dragon Age MMORPG which allowed me to freely explore the continent at my leisure.
I know I'd probably hate it if it were ever created... hordes of kids bouncing around, hitting the jump key 50,000 times and spewing out Chuck Norris jokes usually tends to take the shine out of any imagined enjoyment I'd get from an MMORPG; but I like the 'idea' of it... if not the execution. Perhaps if it were created with some kind of draconian, heavy-handed role-playing ruleset, in which any person caught out of character would be given an instant ban! (which will happen round about the same time as the first manned expedition to Pluto).
To get back on topic though - Things I liked and disliked about DA:2
Story - I actually enjoyed the central premise behind the story and the various intrigues involved - even if it's execution was (I feel) somewhat flawed in many places.
Kirkwall - Generally liked the city, it's atmosphere and visuals. It could have used a bit more attention to detail. it's often the little flavour touches that brings games to life for me, discarded stuff lying around, trash on the floor, signs of inhabitance. Kirkwall seemed a little 'sterile', too unlived in.. but on the whole I found it an interesting place to explore, with a nice contrast between poorer and wealthier sections. Also found it odd how city dwellers in do not, in any way, react to combat, even if scores of bandits are being annihilated under their noses - I've had people wish me 'Good day', as I was busily fireblasting a bunch of assassins. Would it have killed Bioware to add a script which makes bystanders run away when violence breaks out? (we're assuming here that the sheer volume of murderous, psychopathic gangs in Kirkwall, most of whom try to kill Hawke on sight without any attempt at extortion, robbery or other traditional criminal activities is in some way 'normal' for a large city - how the heck do normal residents transverse the city at night? The murder rates must be staggering!).
Outside the city things were different, the Deep Roads in particular - in contrast to the dark, ominous, jaw-dropping look of the DA:O Deep Roads, with it's feel of vast complexity and crumbling splendour - seemed very sterile and empty in DA:2. Bright, square corridors, devoid of personality. I could have coped with the recycling of locations, if some of those locations had a little bit more life and depth to them.
The other thing I liked entails one of the major Act 2 antagonists within the game, who I felt was brilliantly drawn, and portrayed. I guess I can't go into any more details about this character without giving away spoilers, if you have played Act 2, you will know of whom I speak.
The rest of the things I didn't like are too numerous to go into, most have already been stated hundreds of times, in hundreds of reviews, forum posts and user comments. I see no need to repeat them all, most of are well-aware. I regard DA:O as a 'perfect' game, and DA:2 as a 'decent' game with occasional moments of greatness.