I used to think many of the same things you have thought about how the world might be improved. Eventually, I did reach the conclusion that happiness can only exist because of pain, and you can see this, too. If we were to get rid of the feelings of hate and pain, we would lose the ability to feel anything. This is the same thing as going into a coma. I used to think a coma would be the ideal life -- it's the same as suicide, but you can't be blamed for it legally or morally.
I once toyed around with the idea of housing everyone's bodies in suspended animation with only their minds active. It's a lot like the Matrix, but instead of allowing everyone to live out their allotted lifespans and (somehow) procreate, everyone would be kept eternally young, and no new babies would be born. Their real bodies would be below the ground, and above the ground they would have machine bodies that could interperate feelings of pleasure but not pain. Meanwhile, the environment could re-form in its entirety because humans no longer needed to destroy it to make themselves comfortable.
I had the same idea about offing the entire world simultaneously. We have enough nukes, after all.
In the end though, you have to realize that these things aren't going to happen. They are fine ideas, in the same way as Communism working is a fine idea, but could not be put into practice. So we come to the choice of making due with what we have, withdrawing, or suicide. Out of the three, adapting to life on the outside has the most opportunity for growth and happiness, and can be achieved no matter who you are. Even if you say you aren't good enough, you are human, so you can change. All humans can change themselves. Taking the first step is as easy as walking around in a place with a few people. Eventually maybe you'll be able to go into a store and ask the clerk to check out your order at the desk. Then maybe, slowly but surely, you can learn to make small talk with people. It's hard, but it can be done, and it can be very rewarding.