BTN is playing 26/16 over 100 hands with a squeeze of 13% but sample size is very small. 3-bet from most positions is actually 0% so this leads me to think he's still heavily AA weighted here.

I think anything other than check/call here is standard.

I was a bit surprised at the turn check/back to be honest. Now I am not so sure if AA is still in his range, but perhaps maybe more A***ds rundowns, etc.

Now I am at the top of my range since I never get to the river with a straight here. But I block the hearts and I think if villain was squeezing with A-high double suited rundowns then it's possible he hits this river. Also the pot is quite big and I have a lot of KK** in my range so I don't think he ever bets two pair on the river for thin value.