[Lloyd]

Hand 1
2.5 to 1 odds. I'd say that's just about good enough to call with proper odds if you hit an A or K. If he has QQ/JJ you're probably not getting paid off if an A or K hits so you're pre-flop pot odds are probably your implied odds as well. Since you should make an A or K a little over 1/3 of the time you're just slightly good to go in that respect.

Personally, I really hate putting in so much pre-flop out of position with AK. And I usually don't mind busting out early for a chance to double up (or win a nice pot pre-flop). Throw in a slight chance of a loose call with AQ. So this advocates pushing.

I definitely think calling is better than folding so I think you either call or push and both are reasonable. Sorry, no clear answers all the time.

Hand 2
Marginal call pre-flop. You barely have the right odds to call for set value if you can stack them. This is the best flop you can hope for without flopping a set (obviously). If you're going to play past the flop you need to get your chips in the middle with the most folding equity. Making a normal bet will get re-raised all-in by an overpair. Pushing will get called by an overpair. Check-raising is your best option (if you're going to play).

When it gets back to you on the flop, the pot is t890. I'm sure you're up against an overpair, possibly a set but not as likely as the overpair. But MP3 cold calling does have me a little concerned that he could have a set. So you've got 8 outs to make a straight, you've got 2 outs for a set which may or may not be good. You need better than 2 to 1 odds to make this +EV. I don't think you're getting that much if you push. So, I'd fold.

Hand 3
Fold. If you're in LP or the blinds then a call makes sense. But you can't just call, you'd have to push and there are too many people left to act for me to feel comfortable doing so.

Hand 4
I'd fold this as well. Yes you're getting shortstacked but you just paid the blinds, are not desperate, and should have a much better opportunity later on.