I'm not an EV expert, but I think I posted in the next thread what the likely hands who hold on till the river are - the turn isn't likely to help any of the hands that would call the flop, so just look at who would limp PF and call the flop bet.
AT, AQ, AK - possible for them to call down the flop/turn, so they'll still probably call the river if Hero doesn't overbet.
AJ - yeah, they'll call down, and probably raise a bet on the river, figuring they're ahead with top 2 pair
44 - yeah, baby set is thinking like us (but behind), he'll at least call a river bet, and maybe raise it.
QQ, KK - possible, but not likely (call the flop/river with an A out there and 6 people playing? - not likely), especially with the PF limp.
AA- no way with the PF.
and the 4 possible better hands -
JJ (should fold on the flop or turn)
non nut-flush (called an over 1/2 pot bet on the turn - lousy odds
for them to call)
straight draw (calling the turn bet for a gutshot? I doubt it)
nut flush - most possible better hand. But if you had KcQc, wouldn't you raise on the flop? I would, if only to block a turn bet.
I still say the only logical hands for the opponent to have are AT-AK or 44 - all of which are behind, so bet this one, because most of those hands will still call.