Both villains are regs, UTG is opening 16% of hands, BU is a tight 16/11 reg who is propably flatting 10% here minus polarised 3-4%.

I believe my line up to the river is very standard, I think either of them is likely to stab the turn with a FD or a straight (this deep it's also not unlikely either of them has checked back flop with second nuts and no redraw). If not I still can bet or c/r river depending on cards and tendencies :)

River brings the frontdoor flush, not sure if I can valuebet against his range here or maybe induce something stupid by betting rather than by checking. Spot doesn't look like one villains would be very willing to bluff vs. a check.

If we wanna bet, what sizing do we want to use? I would want to go with ~40% Pot to get value from weaker parts of his range and maybe induce some, since bluffing doesnt get really expensive for him, and the times we have hands like AQJ:ss we can bluff cheaper.