I'm glad that Chewie survived but bringing him back (or rather, the way it was done) was kind of silly, in my opinion.
Actually, Rey accidentally killing somebody she was close with could have made an interesting theme - to the point of "shattering" her and pushing her to the dark side (with Kylo's assistance). Though that would have probably been better explored in an earlier part of the trilogy.
So, come to think of it, they didn't really do much with Chewie's "death" - I don't remember it having any remarkable effects on any of the other characters. So (similar to Threepio's sacrifice, I suppose), that plotline definitely caused some shock (both for audience and characters) but it seems rather wasted