3 to a flush on the flop and OESD- dump it every time, and twice if there is a baby bet (baby bet smells of made hand hoping to build a decent pot by not scaring anyone away or a weak semibluff to the nuts). First, your outs are not clean as 2 of them will put 4 to a flush on the board. Second, someone is sitting out there slowplaying a made flush which can cost you a lot of mony in the event that you make a beautiful second best.

If you have a pocket pair and not getting any action bet the damn pot. You'll be surprised how often your made hand is best when the flop missed everyone. However, you just have to use common sense, how many people are in the hand, how many overcards are on the board and how likely is it that one of your opponents are holding one of the overcards? You are making that play to win the pot right there and have no intention of "drawing" to a set.

Dump the J6 every time in NL. Drawing to a draw is not even a good idea in limit unless there are 6-8 people in the pot. However if you have the AJ or any 2 overs and are sitting in late position with no action in front of you, there is nothing wrong with trying to buy the pot, just don't do it with one of those weak minimum bets.