Every now and again, I'll find some new programming font and try it out, retrying all my other installed fonts. Retesting is important as my display setup (and vision--can't read 2880x1800 native on Macbook anymore) have likely also changed.

Now using Fira Code Light in IntelliJ/RubyMine dark theme, size 14, line spacing 1.05 with ligatures disabled.

Before that I think I used Input Mono since it came with so many widths it was pretty easy to find one that hit a mark.