pretty sure it's super standard to call,call,shove IP here especially since your calling with MOST of your range and this keeps your range the widest but that's a whole different point all together.

Calling also keeps his range the widest(bluffs,semi-bluffs, all his Kx we'll still stack eventually, smaller pairs).

The only way not slowplaying would be better is if villain isn't going to bluff later streets and is willing to continue w/ flush draws once we raise flop/turn or w/e. Once the flush gets there you can probably just try and get it in now before another diamond comes off or w/e. But shove the river for sure once he bets or just bet something small when checked to.