If you miss the flop with three suited cards throw them in, even maybe with two. You always need to play AK aggressively. If the flop is unthreatening then make a good raise if you have one or two opponents still in the hand. If they reraise then throw it in, it's a fairly profitable semi bluff that often can take the pot. Be careful against calling stations who will call with a small pocket pair or low pair on the board, who have an advantage on the turn and river.