I liked Catwoman. As you said, she lacks all the versitility that Batman has, but she is fun to play as anyway. I liked grappling up walls with her because it was like climbing the wall as opposed to ziplining up it. She could have been more fleshed out, but being as she's being considered DLC, she's pretty good.
I tried out TAS skin, and I got to say, it's pretty cool. It felt out of place in the highly detailed environments and whatnot, but it looks great. I wish I could get it in the campaign before I beat it though. That's the only downside I could find with it, other than that the fabric wasn't a dynamic black/blue like in the cartoon, but being it's an add-on, it's not a big deal. That would have been a pain to program though.
I'm very impressed by the game overall. Very well done, and the improved fighting and gliding mechanics are great. Pitching took a little while to get used to, but it's fun. My only gripe thus far would be that the new remote control batarang is freaking crazy; I hate how it's inverted controls(might be changed, but I haven't found that option yet if it is there) and it just feels too sensitive compared to the one from AA. Smoke pellets are cool, and so is the taser gun.
I saw gameplay of the Batman Beyond skin as well, and it's done very well. His wings are retractable and he has a nicely done matte black finish. He's on the muscular side, but I believe it's supposed to be Bruce using that suit, so it makes sense. My only complaint with that one is that his chin is very skinny compared to the original design; whether this was done to emulate Terry or not, it simply looks weird. Also, if it is Bruce, I would expect his chin to be the same size, no? Yes, I know, it's DLC, if you don't like it don't buy it/ be glad it's there at all, etc., but it just seems like a minor inconsistency.
Enemy tactics during stealth areas have been improved from the first game, for example, they carry NVG, which allows them to see Batman perched on gargoyles.
AC so far has improved on all aspects of AA, and it is definitely worth your money. Catwoman's levels could have been longer and more plentiful, but I guess that Rocksteady was more focusing on Batman than Catwoman, so it's ok. The game is great, and there is a ton of stuff to do in it.
I'm looking forward to Robin and Nightwing, that is, once I beat the campaign; could be a while(yes, it is pretty long).