i have a kennedy proof question advice appreciated.

I think you are confusing the concept of "frosted" with toning. That is toning you are rubbing off. At this stage, its looks like a haze. The frosting happens on the devices as a normal (intentional) part of the proof creation process at the mint. The haze / toning you are seeing in the fields on those proofs coins is a natural occurance that happens with time and sped up / decreased based on how you handle and store the proof coins.

I think most people find some types of toning attractive, but I don't think the haze you are seeing on those coins is typically considered appealing. Still, I would leave them alone and not rub them off.