You probably shouldn't be calling the UTG open with JTs here if BTN is really aggressive. Calling becomes viable if the table is passive, but even then rake kinda kills the EV you might get.

River is just a shove I think. It's certainly possible that you're beat but I think your hand strenght is enough for shoving. If villain 3bets a lot then he should have a lot of Qx/JT to call with. He might also find a call with stuff like AhAx.

If you do check, I think you have to fold to a shove. Shoving yourself is certainly better than check/calling in a spot where it's really hard for villain to have bluffs.

Folding preflop seems better than calling without good reason to expect significantly higher EV than in general.

Postflop all three your decision points are pretty interesting.
OTF I guess XC is the safe and standard play, but XR could be better versus a decent amount of villains.
The turn usually isn’t neccessarily Great for Hero, however since you have JTs in your range where I wouldnt this might be a fine card range vs range for you. Versus villains that tend to check back OTT with their overpairs (low turn barrel frequency in general) leading is an interesting option. Not sure about your polarizing sizing, might be fine? You balance this with blufs? (JJ/TT?) or just purely with nuts as an exploit?

I totally agree with Samu his line of thought OTR. Not sure if you can valuebet, but surely valuebet must be better here than XC.

You're deep, I don't mind call pre and play the post flop.

Both XC and XR OTF seems ok, I'd mix both lines.

I don't know if a donkey-bet range is good, the most standard way would be XR the turn as played or bet the turn if you XR'd the flop.

River I'm confused. Villain won't have many value combos. AhKh may get there, QQ has one combo only, 99's 88's and 44's probably call pre and play multi-way. AhQx may turn his hand in a bluff but at the same time has a good showdown value, I don't think other AhXx gets there on the river and tries to bluff.
I'd go for full value and shove the river myself trying to get called by worse combos plus bad calls that would check back on the river.

Anyone have an opinion on chk-raising the turn? With the flush draw being brought in I highly doubt villain will slow down, especially considering that he's representing a Q/Over-Pair here more than anything.