Question 1: After reading the above, my impression was that we should play our medium-strength hands as a bet/fold on the flop followed by a check/call on the turn. The flop texture doesn't indicate that he would be raising often on the flop, which keeps all of his strong hands in his river range. Coupled with his aversion of bluffing in 3-bet pots, I think the river is a check/fold if we don't improve given the strength of our line.

Question 2: After reading the above, I thought that some portion of our best air should be played as a bet/fold on the flop followed by a bet on the turn if we improve at all. This is some of our best air, so I think it's a bet/fold on the flop leading to a bet on the turn to try to take advantage of his weak turn range. If he calls on the turn, I think it's a check/fold unless we improve to 2 pair or better since at that point I don't think he's folding any of his range to a shove because he doesn't like to raise the flop so all of his strong hands are potentially still in his range if he doesn't raise the turn with them.

* After answering question 4, I think an improvement is to make the turn a check/raise if we improve to a gutshot or better draw. His turn range is particularly weak after he calls the flop and bets the turn.

Question 3: Because of his flop tendencies, I think this is a check/fold on the flop followed by a check/call on a lot of turns. If he's value betting so much on the flop, that means that when he checks his turn range is going to be pretty weak. Couple that with how much he seems to like bluffing on the turn, and it's possible we should check/call the river as well given how weak his range from the turn will be.

Question 4: I think our strongest hands should be a bet on the flop to take advantage of how wide his calling range is, followed by a check/raise on turns that put more draws out there. If the board is particularly dry, I think a check/call is fine on the turn followed by some combination of bet/calls and check/raises on the river. His river range is still going to be fairly weak, so it's possible we get more value from leading with another check than value betting, and while I'm not sure, it's what I'm leaning towards.

Question 5: This is one of the weakest holdings we'll usually have here. It's going to be hard to make a flop bet profitable, so I think the flop is a check/fold. Once he checks, I think we can bet a lot of turn cards that improve our hand to a good draw or a pair (including Aces) but expect to get called (or raised) a fair amount of the time. A turn check/raise doesn't make any sense because we'd rarely [never?] take this line for value. If our bet is called on the turn, I think we value bet when we improve to two pair or better and bluff a lot of scare cards because his range seems to be a lot of low pairs, draws, or hands that caught a pair on the turn (since he value bets so much on the flop but checked instead).