AWHP superheat & sub-cooling

[desA]

SH, first priority is to ensure "No Liquid return"

Fair comment.

Max SH is 25C, but not at all conditions,

Did you mean to say max temp return is 25'C, or really max SH is 25K?

Bigger the compression ratio the smaller allowable suction sh, (lower discharge) smaller comprssion ratio higher allowable SH. All limited by motor current.
I would say if your dicharge temp was under 105C and your moter current was 5% less than the name plate FLA, you would be pretty safe.

Fair comments.