Obv take this with a very small grain of salt:

H1- I play the same. His flop donk is something I see a lot with like 99 in this spot, which I never expect to fold and such.

H2- I would pretty much c/f the flop, mostly bc their ranges are really ambiguous and further betting to better define them is probably building a pot I rarely expect to win, if that makes sense. Is it a leak for me to just not try in these spots like evar? With the guy playing half his hands in the pot I would just wait for value betting opportunities and not try multi-street bluffs against someone who has already shown the propensity to call more than he should.

H3- I think that ppl tend to not respect the bet/check/bet line when I take it and to me his range seems more heavily weighted towards 2nd pair pps and weak Queens (on the flop) than straight draws, so b/c/b becomes a viable line for more value hands, but like you said we aren't really expecting him to think that way.

H4- The likelihood of him having a FD on the turn is really low, right? We have the As so that seems to eliminate most positionally aware players' flush draws on this board. Given that I don't think there's really anything to be concerned about except how to get the money in smoothest.