[Unarmed]

It's fine.
He's either drawing, has two pair, or a boat.

I'd be hesitant to assume the latter as he'd normally bet the river, but then again you've shown strength throught the hand so a check-all-in isn't completely out of the question.

Two pair is just unlikely here due to the slim odds of hitting it.

A busted draw is by far the most likely holding here, followed by a boat, followed by two pair. (IMO)

Given that read, I wouldn't be betting anything on the river as the only hand that calls you is the hand that beats you. (ignoring the slim chance he's on 2 pair)

Alternatively, you can bet some small amount and force a 2-pair hand to make the crying call, which is what you did. Its a riskier play though as it gives the boat a chance to CR you all-in.

There's some advice! Unfortunately my ROI just dipped below 30% (!@#!$!@#$) so take it for what its worth.

EDIT: Flop and turn play are obviously fine. I rarely slowplay trips without a bulletproof read...especially here when there's a very good chance opponent is drawing and your hand can't afford to give a free card.