I used to love tiling window managers. But I found out that UI heavy applications (those with a lot of extra things around the data itself, eg an IDE with toolbars and stuff around the actual editor) don’t seem to fit well into half a screen, so I prefer to use a predictable arrangement where for instance the left and bottom bit of my terminal is visible even though part of it is obstructed by the web browser. (Then I can click the web app and see if the log message I was waiting for appears in the terminal.)

I use Hammerspoon for this and I have keyboard shortcuts that will move the window and resize it to a predefined position. And I have shortcuts to select certain apps quickly.

Hammerspoon is scripted in lua so I don’t feel very constrained in what I can do.

There is also Phoenix, it uses JS.