>>2056251
>possibly convert it to a 1x10 or 1x12
Do that.
In my experience, this is what makes these builds ride great like a modern bike.
I'd recommend a 40t chainring, I feel that gives a nice range of gears. I've never felt that I needed more, and I do technical climbs and road sections with my builds.
If you want to keep the budget low, get a microSHIFT cassette/derailleur/shifter combo. Their stuff offers a lot for little money.