Hand1:

I have no reads. My only read is that villain is not a reg.

Stacks:
UTG ($584.70)
CO ($620.40)
BTN ($1366.60)
Hero ($609.00)
BB ($644.51)

Pre-flop: ($9, 5 players) Hero is SB [Ad]
3 folds, Hero raises to $21, BB calls $15

Flop: [Th][2s] ($42, 2 players)
Hero bets $30, BB calls $30

Turn: ($102, 2 players)
Hero bets $76, BB calls $76

River: ($254, 2 players)
Hero checks, BB goes all-in $517.51, Hero goes all-in $482
Again, he was fastcalling me on flop and turn which lead me to believe that he had a draw. And then on river he instashoved. I mean even A4 or 44 or 55 needs to thing a little before shoving there. Its not that of an easy decision. Again, I usually advise folding here but I just want to make sure that folding here would not be weak against unknowns. Bluffing component seems big since river is a perfect bluff card for missed draws while 99% of hands that have me beat would raise at some point prior to river.
call/fold? We need to be right 45% of time here to make it worth the while.

Hand2:

Stacks:
UTG ($725.80)
Hero ($714.65)
BTN ($518.00)
SB ($761.90)
BB ($582.00)

I'm having trouble with getting 3 bet by players that play 15/12 in blinds. They are trying to exploit their tight image and are 3betting me quite liberally with any PP from blinds.
I'm not sure how to battle this. Folding could be a solution but I don't know if that is weak or not?
Pre-flop: ($9, 5 players) Hero is CO [Th]
1 fold, Hero raises to $21, 1 fold, SB raises to $70, 1 fold, Hero calls $49

Flop: [4h][7d] ($146, 2 players)
SB bets $80, Hero calls $80

Turn: ($306, 2 players)
SB bets $160, Hero calls $160

River: ($626, 2 players)
SB bets $451.9, Hero folds
Obviously I'm getting well milked on these streets and he can quite well bluff this river knowing that my range is 99-AA and i will most likely fold 99-JJ to his shove, even thought his betting pattern indicates a value town rather than bluff.

Hand3:

Stacks:
UTG ($1205.77)
Hero ($609.00)
BTN ($945.00)
SB ($882.67)
BB ($120.00)

Pre-flop: ($9, 5 players) Hero is CO [Ac]
UTG calls $6, Hero raises to $27, 1 fold, SB calls $24, 1 fold, UTG folds

Flop: [4d][5h] ($66, 2 players)
SB checks, Hero checks. Now the reason why I checked here is the fact that there are many regs and fish that love attacking flops low flops or flops where I'm unlikely to have a hand. I get played back here so much and I cant stand a raise while I do have a gut+ 2overcards.

Turn: ($66, 2 players)
SB bets $54, Hero calls $54
So now the question is should I raise here or just call?

River: ($174, 2 players)
SB bets $162, [i]Hero folds[/i
I decided to fold here since there are not many hands that I beat. Im not sure that Kx bets that river while both 76 and diamond draw got there. There are practically no hands that would bluff except Kx thinking that he is valuebetting.

#1 your check induces bluffs and you mostly have to call, but I don't like that overbet by him. Do you see a lot of 2x pot river shoves at your site? I don't, so I'm not sure what to do here.

#2 Isn't this a raise or fold flop? I want to take control, and if he has JJ-AA he won't let me so I can get away cheaper.

But more basically ... why do you think "they are trying to exploit their tight image"?? Why can't they just be tight? Do you assume that they assume that you are running PT?

If they are 3-betting any PP then shouldn't you be (considering) 4-betting this preflop since you're ahead more often than not? Since they could have any PP, there are no good flops for you except those containing a T: a 742 flop like this and all of a sudden the # of starting hands that are ahead of you just went from 3 to 6.

#3 Tough one.