Good posting Vi,
Ive had some similiar thoughts on isolating and i vary my iso's by a bb + or - depending on what I wanna do and esp based on fishes/limpers stack ie less if he has 60bb etc. I dunno much about US sites but are there very many reisolations?? what i mean is yu iso a fish then someone 3bets you with crap since they know your raised is vulnerable.
i say ''crap'' bcoz they shouldnt be raising mid strength hands since they can call and crush fish thus only premiums and crap raise.