Good luck mate. I remember switching to 6max and how it hurt, so I sympathise. But then I didn't have the luxury of such a BR cushion.

BTW have you considered dropping down to say $100NL while you learn? The play is slightly easier and if you're going to be dropping a buy-in or two you could at least drop them to me

As for the hands I think I'd probably want to be 3-betting most often with JJ in position. If he calls I'd usually feel okay with pushing that flop.

AK hand. I'm not sure about the turn re-raise, of course. But I'm even less certain about the fold. I mean you're getting good odds, are you THAT certain he has the Ah or a boat often enough to justify the fold?