Interesting debate there. I think as far as the Mr Mcmahon character, the impact of it and just how convincing Vince was in the role (partly because a of it was him), you could argue that he should be up there. Then again you might argue that he kept himself in the spotlight too long, and that the constant nicking other people's spotlight and wrestling far too many times did soil things a little, also the character did get stale after a while.
Linda has just never had the personaity to be a on-screen performer and to me always looked uncomfortable in the role. Although Shane and Stephanie faired better, they still were far from their father's league.