Considering the unknown vs. unknown dynamic, flop probably leans more towards a bet than a check. However, assuming we had AK here, would we occasionally/more often than not want to check back as well and try to get additional value later while pot controlling? This doesn't seem like the type of board to get 3 streets of value from an UTG limp/call range which would favor the check. Seems like an exploitable spot in the sense that we are checking our made hands and (semi)-bluffing all non-paired hands.
OTTH
Effective Stacks: $550
V1 ($550) limps UTG
UTG+1 ($550) limps
Hero ($550, LJ) raises 76 to $30
HJ, CO, BTN, SB, BB fold
V1 ($550) calls $30
UTG+1 folds
Flop ($65): A
4
5
V1 checks
Hero bombs away for $50
V1 calls $50 easily and eagerly
I can't decide if this was a mistake or not. More often than not my default c-bet size here would be $30-40. Now in my head I was thinking "I am an unknown, so bet large so that if villain did flop a set or two pair he lets you continue bombing away and overplaying AK" rather than betting smaller and forcing villain to have to take matters into his own hands with a x/r to force the action.
But since he did call all too eagerly, I've gotta assume villain is pretty strong here and it's time to slow down until ...
Turn ($165): 3
*BINK*
V1 checks
Hero ... ?