Pefectly fine to flat pre, 3betting +EV obv. Call against the small 4bet ok.

Postflop: A simple answer to ask yourself is, "do i want to get stacks in?" the pot is already too big to have much room to maneuver. So if the answer is no, you shouldnt bet flop at any size. You dont need protection against this board texture, against a hnad like KK, you can go for thin value OTR.

Pre seems fine.

I think okay to bet the flop sometimes especially when U have a bacdoor also. U can ch too.
I think I bet a bit bigger.

As U played the flop now U can ch the turn, (or U can shove if U bet slight bigger on the flop).
As played also okay I think, maybe little bit harder to maintain balance, but some opponents maybe play worse vs this size because it's a more rare play I think.

I assume U have most of the AQ, and some two pair, and AA occasionally.
He does represent some AA maybe, QQ, A5 occasionally, some A9, maybe he can turn KK into a bluff sometimes or K5dd, mabye he can overplay some Ax verus Your play but he hardly represents bluff.

I think It's okay to overfold the situation.

I kinda like the idea of flatting in pos and actually play my hand with a bigger SPR. Maybe my game idea is outdated.

I've seen a lot of players x/s w/ AK type hands to get value vs draw or the exact same hand u have.

On the flop, though, I don't think the hand is 3 streets value hand, we have AQ, A5 a lot here. Moreover, villain doesn't have not much thing to call down worse.

I don't see any merit in betting the flop against an strong/polarized/uncapped range, in 4bet pot you def want to go more polarized

I don;t think you should be betting flop or turn. AP fold turn. he's shoving because he scared you are going to check back the river.