Roxas and Xion are the only unlikeable ones.  Mind you, most of the story focuses on them, sooo...
Yeah, needless to say, being the KH "fanboy" that I am, this one's been on preorder since July.  Movement with the D-pad is a little shaky, but other than that, the gameplay is nicely-done.  And the story can't be bad if none exists.  It just seems like it's jumping from one day to the next, whacking Heartless.  So if you call that a story, then I would agree, it's bad.