Can you explain why playing my actual hand's strength is horrible here? I felt that some showdown value hands should be checked back on all flops because I can't cbet them all the time. By checking back, I can get stabs or a vbet myself from/targeting straight draws on the turn. If I do it on the flop, those hands aren't really putting money in bad since I don't think I'm double barreling this thin. So I wait for their equity to cut in half and get money in. That's a concept I kind of learned in mathematics of poker, but it was in limit. If they'll put in money on either street, I'd rather do it on most turns when they're not getting the right price. I felt a lot of the hands that called were not going to be worse.

Preflop I'm getting called by any two cards that will over call in the first place…which is like…a lot of hands for this site. I think I'm in the middle there. I don't know. I think he'll stab air more than he'll value bet. As it turns out, villain had K3o. I don't intend to be results oriented, but I think it's difficult to say playing my hand is terrible when the villains have a lot of air on the flop.

While 33-99 almost certainly fold, the fact is villain had K3o here. This villain is going to have far too many hands for those to be entirely relevant. 

33-99 is 42 combos of hands. K3-K7 alone is 60 combos. A3-A7 is 80 combos. 56+67+78+89 is 64 combos. Like we're all over the place. If villain were a tougher player, I'd agree they can put me in tough spots. But a weaker loose passive villain will stab once at some point sometimes, or just check it down. They'll check/call the turn with a draw. They also still have a decent chunk of Qx and Tx I'd imagine. That's probably like 100 combos. 

AT is a way better hand to check back, I agree.