The whole "ILM or WETA would've done it better" argument is tired because no movie with that amount of effects will look real. CG only looks real when the majority of what's going on around the effect is real/practical. Then animators have a baseline of how detailed they really need to get. People always use the prequel trilogy as their example of bad cg, well what company worked on that I wonder? Lord of the Rings looked great BUT they used real locations and a lot of practical effects like miniatures and then highlighted them with CG. Avatar was one big cartoon, so much so that they had to change the way the actors looked to make them look like they were even in the same world. The point is that, even as far as the tech has come, it hasn't come far enough to create a completely realistic looking world. CG isn't good enough to fool the eye, not yet.