Currently using the following:
- Karabiner
- https://pqrs.org/osx/karabiner/
- Seil
- https://pqrs.org/osx/karabiner/seil.html.en
- Hammerspoon
- http://www.hammerspoon.org/
Using the above tools, as many have, I have mapped my Caps Lock key as a 'hyper' key that simulates pressing 'shift,ctl,alt,cmd' at the same time. I have then defined functional sequences (hyper + <key>) to manage windows and focus/open applicaions. For now this is a very basic setup but a good starting point to understand exactly how each component works with the other and must be configured.