Korthrun

Tiling WM that you are not sure you want to get into: Sway. It’s a great alternative to i3 IMO.

What I use when I care to put in the effort of setting something up in great detail: Enlightenment. Some may argue that it’s not “lightweight”, but you can readily include only the bits you want, and avoid things like network config guis and system tray apps or whatever it is that you don’t want. Even when you’re using “all the things” which is not technically “lightweight” what it IS is performant. Oh, it’s also very pretty.