No matter how many LOL's you add I will still not consider it much of a "slowplay" because it was only preflop. If he had check/called the flop or turn, then yes.
I agree that he should have check/raised the flop instead of leading out. I assume he made the weak lead looking for a raise, and if you had AJ, QQ, KJ or something that's probably what he would have gotten. And he would probably have stacked the average player who had TP there. And why would he overbet such an innocent looking flop? The only real draw is for 54, which is a pretty damn unlikely hand.
3xBB is not a miniraise. 3-4BB is actually a standard raise.
His turn bet is actually very good. A 'normal' turn bet is usually about 75% of the pot, he bets 93% because it is draw heavy. It would be silly to bet more, like you recommend. He has no reason to put you on a 13-out draw. Of course you can call the bet because your hand is so well disguised. If you had flopped the flush draw I think it would have been wrong to call his turn bet.
The river I think he should consider a smaller valuebet, however, you have been calling the whole way and he has no reason to believe that
helped you. Most likely he has you on a top-pair hand and is hoping to get paid off. Your raise is very unlikely to be a bluff, I would be pretty sure you had a set actually, so the call isn't very pretty but he's hardly the only one who can't get rid of an overpair after putting half his stack in the pot.
Other than the lack of re-raise preflop I don't think he played it bad, perhaps he should have gotten away on the river (I hope I would) but you won't find a lot of players who can fold KK in that spot.