For some reasons you disabled auto-pair-mode. I guess it's because of some compatible issues, because I encounter it recently too, with js2-mode.
Emacs 24 comes with electric-pair-mode, which is stable and satisfies my needs. You might consider give it a try?
Of course it's your configuration, I'm just giving some suggestion ^_^.
Thanks -- I'll give it a try!
Enable electric-pair mode if available (see #75)