regarding flopped sets: At this level, hitting your sets should earn you big money. Just bet them strong and the fish will pay you off to chase their flushes. Under no circumstances should you check or bet less than 2/3 pot when you flop your set. If the board is suited on the flop, still bet it strong but if you get called and the turn or river hits a 4th flush card, then dump your set. Otherwise, it's hard for me to see flopped sets as a 72% losing situation.

regarding your last paragraph: I think the key point is feeling out the table and individual opps. If people are consistently raising 3-4x in late position at your table, then you are not in a loose calling table type of situation that my strat would work.... so you're definitely right that you'd need to tighten up based on position and opponent.