I didn't read your entire post, but I'm guessing you're complaining that the character and equipment power increases far too much with each level. If that is indeed your point, I fully agree.
The power level increase per level is on an exponential curve, and it gets out of hand fast. Even in the early teens, I'd upgrade my legendary weapon to another legendary weapon one level higher, and my damage output from that alone increased by 25%. That's ridiculous! Fights that were nigh impossible are suddenly cakewalks just because I'm one level higher. That shouldn't be.
