In my opinion, it had the worst sound (follies I think is what movies call it) that I have ever heard from such a high budget movie.
I think it was successful because of its use of 3D which hadn't been used like that up until that point. I think Disney had a lot riding on 3D being big, heck, back when this deal was made, Disney had Camron's company producing ESPN's 3D broadcast...a lot has changed since Avatar came out, changed since 3D TVs never took off, it is a different world today.
I am sure people will love this land, I am sure Camron wants Avatar to be his Star Wars, but not everything can be 'created' and need the public to believe or bond to a franchise for said franchise to become a mammoth like Star Wars.