Right, I think my thoughts have been confused by the two big changes in HF19... but may have understood now:
The perceived self-voting increase doesn't have anything to do with the change to linear rewards, but is purely due to the increased max. vote power making it more practical, and noticeable.
To implement the quadratic voting more appropriately to reduce self-voting (the way the white paper claims to support), the maximum vote power of an account should be proportional to the square root of SP, not the square. So moving to linear was a step in the right direction, but not far enough.
It would of course encourage sock-puppets though. It seems there's no answer to that in an anonymous system.
Is this your thinking or am I still missing the point?
I think you are in the right direction. I am not an expert myself. I just happen to know a lot about the diversity here.
Ideally, an entirely different voting schemea might be what is best.