That's not the only reused aspect of the film, though.
He reused a ton of elements from his own films such as Aliens or Terminator 2 and did so in a way that, I would argue, made Avatar feel rather stale and unoriginal.
I would also argue that the movie is overlong and have several minutes of scenes and footage that does very little to progress the overall story, and that interrupt the overall narrative flow of the film, both reducing its quality, and making it harder to stay engaging and enjoyable upon multiple viewings - especially when presented in 3D.
Additionally, his method of including a moral message of environmental conservation was done in an extremely heavy-handed and amateur manner. Anyone with any thorough knowledge of creative writi would know that purely by having the film be about outside invaders attacking a defenseless, "green" planet, is enough to illustrate the evils of environmental destruction and upheaval. Multiple scenes, subplots and expositions to drive that point home even farther is exponentially pointless and belies the creative intelligence of the film's production team.
So yeah, my complaints go far beyond it just being Pocahontas.