Yeah, they all seem ok. At least, much better than DA2's companions. I didn't dislike them, but... like, Aveline, Sebastian, Fenris, Varric (I think), and the new dog are the only new companions. Everyone else is from Origins or its DLC, and they're so different in terms of personality that it's kind of jarring.
I can't really pick a favourite for now, because we don't really know too much about them. Arguably the best part of Bioware's games are the characters and their own arcs and stories, and while Dragon Age has always let them take a back seat in preference for a legible, sane story as opposed to their usual writing which branched off into so many insane subplots that it made me dizzy, it seems like they're going to be the main focus again.
I suppose if I had to pick one I'm slightly more interested in over the rest, I'd say The Iron Bull. Because most of the Qunari the player has met so far have been stony-faced assholes, so having a more relaxed one would make them a little more sympathetic.