Hand 1). I would look at villain's bet sizing. <1/2 pot on turn, ~pot on river. Looks strange and i would look him up. This could be a missed flush or a tota bluff.

Hand 2). The thing about regulars and 3betting is that one specific hand could play entirely differently given previous hands during that session. For example, if villain had 3bet you several times already and you had folded every time, this would be a good spot for a 4bet. I don't like to take a weak-medium Ace to a flop in a RR pot since when an Ace hits it is tough to know whether you are against 9-9 or A-K when villain c-bets. Folding is almost always my default play in the beginning of a session, since i like to foster a tighter image so when i play big RR pots my bets get respect.