Cons: -Plot: 4/10. This is not a movie to be seen for the intricate, nuanced, complex, or unexpected plot. It is predictable, unoriginal, and there are very few twists that you won't see coming. The few details that could have made the plot a little more interesting/memorable/creative are not included or expanded upon in the movie, and the vagueness of these details only emphasizes the general lack of though-out plot. (what unobtanium does, the situation on Earth, etc)
- Characters: 4/10. Pretty much all of the characters are steroetypes, or caricatures, or your overused simplistic movie types. The reluctant- hero ex-marine who wants a new beginning. The marine vet who just wants to blow up the place and 'be home for dinner'. The snappy yet good-at- heart head of the science program. The dumb, money-obsessed head of the corporation. The nerdy friend in the program. The innocent, naive, yet powerful and spiritual tribe that is at one with nature. There is very little to no character development, and pretty much all characters can be summarized in a sentence like above, all stereotypes.
Its one of those movies where it is much too clear which side the filmmakers want you to be on. While this is OK in certain movies where this is much more specifically linked to characters in the movie (for example, Oceans 11, and even then, one does not really hate Terry Benedict), in movies like Avatar where its too generalized (humans vs Na'vi) it gets on my nerves. Its too much of the 'violent bad humans who want to destroy the place for money' vs the 'naive, beautiful, spiritual, tree-hugging native tribe that is forced from their homes' in my opinion. There is no nuance or finesse to the plot or premise.
Conclusion: Should you watch Avatar? Yes, you should. At least once, for the unique experience, the visual spectacle, etc. But its not a movie to watch over and over, and don't expect a nuanced plot, developed characters, etc.