I'm just wondering if it's worth setting up payment for?

Bugger all so far. Think one problem is that people are asked to pay before they've even played the game, which is a bit like deciding how much to tip the waiter before you've had the meal.
It doesn't take long to set it up, so you may as well but- unless you've got a big preceding reputation (like Radiohead when they release PWYW albums)- I'd set your expectations pretty low. 

It doesnt take long, and at least it gives people an option to show support. but unless you hit a homerun, you won't make anything even worth cashing out, and then you need a paypal to cashout which you do sort of have to jump through hoops to setup an account there. Also, because Itch isn't based in my country, I got a call from a bank or govt thinking my identity was stolen. I likely wont cashout any money I make here, and I hope it's possible to just use that money to buy other games on the site (havn't tried yet)