It's a pretty wet board to be calling down turn and river, does the Villain have any previous with you or have you shown down bluffs so far? If you are repping a K your river bet seems bluffy in size as what are you hoping will call? I think a 1/2 pot bet or slightly less looks more like a value bet if you are repping a K.

Also, how many hands do you have with a K? AK, KQ, KJ and K10?

AK, KJ and K10 might check the flop, he has blockers to AK and KJ and when the 10 hits the turn this lessens the chance of you holding K10. KQ would bet the flop to protect the hand on a wet board so that leaves your only likely range AK out of hands you would PF raise with.

I don't necessarily like his call but I doub't I would bet at all on this pot with 44, there's too much of his range that this flop hits and I think you'd be better of looking for better bluffing spots. Only my opinion though, and I think the balance between playing too nitty post flop and playing too aggressive is a very hard thing to get right, I tend to rely on HUD stats and notes I have on my opponents and if I don't have decent info on either I prefer to play more straightforward which in this instance would be to check it down and fold to any action.

I agree we need to have a bluffing range but the size of that range depends on what we are trying to represent by bluffing here, if we are only bluffing AK which has 12 combos should we not only be bluffing with the same amount of combos also to be balanced? If so then we might only bluff with 2 of our pairs between 2s and 7s, as each pair would make up 6 combos.

The concern I have with saying 44 is a good hand to bluff here, is it indicates 22 through 77 are also good hands to bluff, and we might want to throw in some Ax hands as well, as we start to do this we unbalance our bluffing range as it becomes wider than our value betting range – and here I mean perceived value betting range from the way the hand was played.

I may be overcomplicating the situation, but I think we need to be careful we don't blast away merrily with every small pair on this flop, and if we aren't going to do this we need to have some rough guidelines in our minds of which hands we do and don't bluff with, I'd be tempted to bluff more with my Axs hands as the A has a blocker to hands with a kicker villain might call down with, and would just check small pairs down. I'm just spitballing here, trying to explore how we don't be bluff crazy.