Dragon age 2 had undoubtedly a better art direction than DA, and I daresay a good one, unlike DA1's art direction which was generic to the power of 10. Which incididentally was also the only way DA2 was better than DA1.
Slightly better. I disliked a lot of the changes though.
- Watercolor look is okay but it doesn't really match the serious tone of the game. First game was a Lord of the Rings knock-off, but at least it did it competently and it suited the game.
- Character designs are fucked up, especially the elves. This is so bad that it actually undermines the emotional impact certain scenes have, because I was laughing my ass off at how ridiculous some of it looked.
- Dragon Age II had even more boring corridor levels than the first game. A few set pieces here and there were neat, but the grid-like nature of the levels was a lot more obvious to me (probably due to a lack of time to polish them). Even the city feels like it's built on a grid.
- Retcons to the art direction were weird. Qunari having horns I thought was fine (the explanation of "hornless Quanri" is dumb though), but changing the elves to anorexic Welsh people was awkward. Also the mirror that's a big part of one of the character's arcs looks completely different in Dragon Age II vs. the first game, which makes no sense whatosoever and no explanation is given even though it's meant to be the same mirror.
- Serious lack of variety in environments, duh. Would it have been that hard to build a few more dungeon areas? They did spend more time on the ones they did have, but surely they could have got a level designer to make a few generic caves out of the existing assets over the course of a week, and used those instead.
- Most of the models were reused from the first game and given new textures which did not fit with the designs well, and at least to me, stuck out like a sore thumb.
I'd say most of the good changes were technological rather than artistic. For instance, lighting was improved a lot in the second game (better shadows, ambient occlusion, more dynamic lights, more consistent lights between characters and levels), plus the DX11 effects and high-res textures helped a lot. The base assets themselves look really weak and inconsistent though.
I got the game for free during that screwed up EA promotion and I still couldn't finish act 2 due to boredom. At least if Dragon Age III is open world it should be more interesting.