-How on Earth can it not cost more to send a whole bunch of people and equipment into space for 3 years, pay them a wage that makes it worth going into space for 3 years, pay for these highly expensive avatars and wage a major war than the actual price they'll get for the ununium?
Remember this is 2154 (bottom left corner of Jake's video logs) so space travel could be a lot more efficient. Unobtanium (not Ununium. Unobtanium is an actual term, by the way - not something uncreative pulled out of Cameron's ass) sells for $20 million USD a kilo. There are probably hundreds of thousands of tonnes underneath the world tree. I think the potential to make money clearly surpasses their expenses (and note that they were
certain that they were going to get it. The question is, diplomatically or not).
-They never really explained why the chief decided that Jake was alright. The only reason he had for changing his mind was that he said he was a "warrior". People have been trying for 3 years to get these people's trust, and all you had to do was say you are a warrior? Also, what benefit does it bring these people to take this guy on and teach him the ropes?
What do you mean Jake was right? Anyway, yes, he said he was a warrior of the Jarhead clan. Remember the shaman (chief's wife, Neytiri's mother) had said they have tried teach the Sky people (humans) in the past but their "cups were already full". The people who tried to gain the trust of the Na'vi in the past were all scientists who had their own ideas of how things worked. Jake was merely following orders, without his own ideas. That's why he said "my cup is empty" so they saw potential to teach him their ways.
Also, remember that Jake is
special. Remember the scene where the world tree's seeds, the "purest souls" all landed on Jake? Neytiri was going to kill him (and so was the heir of the clan) but she saw a sign.The shaman was also the one that dictated his death/acceptance. She tasted his blood and sensed his good heart.
-Why the fuck do these people have tails? They don't seem to have any real use and they only seem to get in the way
Are you for real? Did you miss the scenes where the Na'vi connected their tails to the horse? To the flying things? To the tree of souls (where they could hear their ancestors)?
The tail is like a brain stem with all these neuro-receptors at the end. All the trees on Pandora are connected neurologically, like a brain (Dr. Grace Augustine tried to explain this to the corporate guy who thought trees were just trees). This explains why they could hear their ancestors as well because the memories were stored within the trees.
All animals have this neuro-receptor as well. That's why they could command the animals they were riding with their minds ("Shut up and fly straight!"; "Go!"; "Bank left!").
My bad. Too heated up and read wrong. >_>
-Why does nobody punch the main guy in the face? Also, how could any female possibly like him? Or male actually....
Why do you feel he needs to be punched in the face?
I don't think the points you listed are plot holes.