This is complex. It's two different movies posing as a single entity. It starts as a study in prejudice and man's inhumanity. It's classic science fiction, presenting social issues in a manner that is more accessible and palatable to the audience. It will make you think and it will make you feel bad.
About an hour in, it shifts gears into an action film. The action is very realistically depicted and very visceral, not over the top, not cartoony.
In the end it briefly shifts to a love story.
Overall, it is very well done. It has heavy CGI usage, but it is never distracting, George Lucas needs to watch this before he makes his next film. It's occupied by all unknown actors from an unknown director, but everyone does a very good job.
I recommend that you see it.