The first film was my favourite and I saw that in cinemas when I was a little girl, so hearing we would see a return of Jake Sully and the rest of the cast was exciting. I was pleased at the start of the film to see some of the humans that remained using their technology to interact and better the Na'vi enviroment after so much destruction.
I think they have over used the whole 'colonel wants to take power' thing. We saw it in the first film, we saw the action, we saw the same plotโ just tweakedโ twice with some introduction of new characters and creatures.
In my opinion, the introduction of those new characters and creatures was enough to create something entirely different from the first film. Could it have been instead a different tribe of 'Avatars' waged a war against Sullys clan, and could it have been that we find out more about Kitty and why she is the way is?
I know there is going to be a 3rd and 4th film, I hope we don't see the return of humans and play that storyline again. I hope James Cameron gives us something fresh.