Nice write up!

I would like to add https://wiki.archlinux.org/index.php/def...plications as it shows how to even declare new mime/types automatically for files with a specific pattern.

I have myself changed the mimeapps.list in the past, just to realize it was ignore by some DEs. (or updated, yes even the user based config)

From my experience symlinking that file wont work either. All together it seems to be a pretty unfinished solution once you got deep enough.