Actually the actress playing Clary bothers me more --- I don't feel ANYTHING from her when she is talking about her mother -- it's like "now I'm saying my lines" and that's it. I get that she's young, and like someone else pointed out, I'll give the cast the chance to grow into their roles a bit. But I looked her up on IMDB and she's done enough stuff that she should be better than she is.
I say the movie recently, and I wish we could mix and match the two casts! This Jace is so much better, but the movie's Clary was a lot better.