Betting KK on an ace high flop is -ev imo. You raise preflop and get a call. Put opp on a few hands, AQ maybe AJ AKis also possible, but you would expect a reraise or a pp. Being first to act here i would check it, let opp define his hand. The point i would make here is that if opp has the ace then if the flush hits you have a bluff oppertunity. Otherwise its an easy fold if he bets i guess.
2nd hand id bet hard. If u get a cold call then you could be up against AJ or a drawer. Noone else stays in this pot if you play it hard.#
hand3. you have to call here. Too easy for opp to have a flush or two pair. If he goes around calling raises with QT then u wanna play more poker with him! The only hand i fear here is AQ, if he has the flush again get him labelled.
Hand4 reraise here or fold. SImple. look for cheap showdown. Checking the river is soooo bad!