Simon Tatham’s Puzzles is my long-time favourite and recently I got really hooked on Water Sort (though that one is a bit lackluster in custom game generation). I don’t know if these meet the progression or even deep gameplay requirements, but at least they are challenging and more or less polished.

Why not sell it? Surely there would be people interested in cheap hops in a local homebrewing association, even if you don’t want to bother with shipping?

Make lemonade radler?

That’s what I use with a 25 liter pot to boil about 22 liters of wort.