I do not see us continuing here

the board favours villains range... he could have all the pairs, 2pair, A4, Flushes, we dont.... every overcard with a diamond might call as well. so unless you plan to pull the trigger on the river as well your bet will not create many folds.

Szenarios where your hand might be better for bluffing: turn is 5h obviously, or you have a diamond yourself

Agree with poster above, picking up a gutshot on a three flush board is not enough of a reason to continue barreling IMO.