check flops sometimes when you miss with AK (also when you hit sometimes). Especially when the flop is all unders.

With JJ overpairs, just try to avoid playing for stacks unless villian is a KNOWN moron. This means sometimes giving free cards.

First JJ hand, I check turn looking to fold really. What do you beat with 2 overs and 3-flush out? His bet is really small though... sometimes I toss in a raise on the turn here. Folding is not terrible if you think he's bad and passive. I don't like the call if you are just going to fold to a 1/2 pot river bet on a relative blank (you think he has a 3?)

2nd JJ hand is just rough. I suppose you could have checked to PFR on flop, but you don't want to give overs/diamonds a free card. Checking the river might be better, induces more bluffs and you lose less when you call and are behind. Only thing that calls your value bet here (that you beat) are TT and 9X. Stacks are kind of short for a blocking bet (as you can see when he raises).