Okay I came back from watching the movie and dear god it's somehow worse than the first
The only good things in the movie were the visual effects (with some actually cool creature, mech, and environmental designs) but even then it got old quickly and some of the CG still showed in certain scenes. Lang's character was much weaker in this film but their performance at least was good. The daughter (Kiri I think her name was) and the younger son were probably the only other well acted performances in the film and actually felt like characters since there was stuff to them. The human characters also actually seemed to try despite mostly being stock characters. There was also some good action in the film as well. There were also some unintentionally funny moments at times.
Other than that the movie is utterly retarded. It keeps many of the same problems with the first film like the white savior bullshit with Jake Sully who is also a boring protective dad character. He also fucking randomly narrates during scenes to explain stuff you can tell for yourself, like seriously his narration could be removed and those scenes would be improved exponentially. The other characters are stock character types with three exceptions who I mentioned before. Sully's wife is just angry protective mom, his first born son is just Older Responsible Brother (He's also the only character on the protagonists side who dies and has a cliche death scene), and the other kids I forgot to mention are pretty forgettable. There's also a kid who is the Colonel's son who is just bootleg Tarzan and he is one of the worst new characters of the movie with pretty inconsistent motivations. Like for some reason when the Colonel clone comes back to be a father figure to him, they sort of get along but it's a hollow bond. Later for some reason Bootleg Tarzan saves the fucking Colonel from death even though he wants to murder his adopted family who he's spent more than a decade with (since this movie takes place at least a decade after the first one).
The Na'Vi themselves are incredibly uninteresting. They literally are just stock tribespeople and their culture literally is uncreative. Outside of the animals and environment, this supposedly alien species also coincidentally has huts and kayaks just like normal tribespeople. What genius worldbuilding James Cameron. It doesn't help the water Na'Vi bow down to suck Jake Sully's dick because he's so cool. He even became one of them in the end.
The Human villains besides the Colonel are literally retarded fucking Captain Planet Villains. Despite the fact they had survivors from a prior Na'Vi attack, they never fucking adapted at all, never wear any armor and keep the same technology where these primitive weapons can easily pierce and kill people through. The human villains also act cartoonishly evil like this Australian stereotype who loves whaling and wants to kill all the whales for their "Anti-Aging Oil" and its just pathetic. If this human faction are the antagonists, what the fuck are the stakes for any future Avatar movies. Why should I give a shit about this franchise if all the villains are incompetent retards or were already defeated prior. The only new technology that the humans have is Crab Mechs and Echo Location Blasters. There's also the Avatar cloning where they can insert memories and personalities of people into but it's not that interesting.
Everything else about the movie is either mid or semi-competent. Either way if this movie makes a lot of money, it's only because it's the sequel to one of the highest grossing movies which came out 13 years ago. I can guarantee that if it succeeds that Avatar 3 and 4 wouldn't make as much money.
tl;dr Film is like the first one with sprinkles of good things but even worse