I utterly love Hammerspoon.

It's fun to combine with qmk [0], which gives you a bunch more options for hotkeys on your keyboard via layers. I've ended up with a layer where half the keyboard is Hammerspoon shortcuts directly to apps (e.g. go to Slack, to Chrome, etc.) and half of it is in-app shortcuts (like putting cmd-number on the home row, for directly addressing chrome tabs).

Between this and one of the tiling window manager-adjacent tools (I use Sizeup), I can do all my OS-level navigation directly. "Oh I want to go to Slack and go to this DM" is a few keystrokes away, and not dependent on what else I was doing.

[0] https://qmk.fm/