All of those are great ARs to consider . Have you thought about building your own . My most recent build cost just over $1,000
and you can build a basic one for 6 to 7 hundred
. PSA has a very good product http://palmettostatearmory.com/
As for the stock and sight line . I am in no way an expert but its my understanding that the stock is straight because the BCG ( bolt carrier group ) must slide in to the buffer tube ( stock ) In the normal operation of the gun . If it was bent , curved or canted in any way the bolt would not operate as designed . The by product of this design is less muzzle rise .
I to live in C.A. . You can install the bullet button your self . If you live close to a Turners outdoorsman http://www.turners.com/
They tend to have sales all the time on ARs