In the AA hand, I don't think I should bet that flop just so I don't shut myself out of this pot. What's to stop someone from raising me with 99-KK, or even just on a draw or bluff? When he checked and just called on the turn I figured he was either weak or being cautious, since I didn't think he'd check a 7 or overpair twice. The all-in bet on the end made me figure he either had a big hand (KK or better), or that he was trying to take the pot away from me. I incorrectly figured his overbet meant he was buying it. If he made a big move on the turn or a pot-sized bet on the river I would have folded.

Yeah, you can frequently get by with aggression alone playing 6-max. Generally, I will randomly raise some only remotely playable hands once every rotation or two. In PT, my VPIP is at 43% and PF Raise is at 18.24%. 10.24BB/100 hands. This is 4-6 tabling Party/Empire NL-50 6 max.