Not for vim, but in windows I use Autohotkey to translate midi messages into macros. Get yourself a cheap midi keyboard with a bunch of buttons and knobs like

Not for vim, but in windows I use Autohotkey to translate midi messages into macros. Get yourself a cheap midi keyboard with a bunch of buttons and knobs like the akai mpk mini or the arturia minilab 2 and you have a ton of controls to customize for any macro you want. I personally use the minilab. Take some desk space but way way way more controls. Also, if you get interested in modular synths you can download VCV Rack for free and learn about modular synthesis with a small controller for basically free. Or you could just get a razor tartarus or whatever they're calling them now and do similar without the midi part but with razors proprietary hardware and software.