[Girchuck]

Hand 1 - played perfectly on every street. Even if BB does not three-bet preflop with QQ or KK, you still need to push your set the way you did.

Hand 2 - You do not have enough outs on the flop to want maximum bets in, but the flop might get capped even without your help. Still, driving UTG out with a 3-bet is not good for you. Turn is fine. On the river, the only likely hand that beats you is 99. What do you think the MP was calling?
If you think MP is much more likely to call one more than two more on the river and you think MP is likely to call one more, you might consider going for an overcall, otherwise fine.

Hand 3
This is read dependent. MP is probably not pumping a big ace on the turn. Set is also unlikely. So the 4 [img]/images/graemlins/spade.gif[/img] either gives him a second pair or a flush draw with a pair.
If MP is a LAG, I might check-raise the river, otherwise, fine.

Hand 4 - Perfectly fine