Not technically impossible, but also not as straightforward as you assume as Kodi has a number of dependencies and reverting Python2 > Python3 is more than a simple package bump. I have a suspicion that once you chase down everything for that .. you're basicaally back to our LE 9.2 codebase which is Python2 based.
There is already an MPD add-on in our repo so building derivative audio players should be possible, but it gets complicated when chasing all the extra GUI package dependencies for things like Apache/Nginx. I'd like to see it done though, as all the ARM/Pi audio projects (Volumio/moOde/etc.) are using desktop distros as their base and 400MB images sounds a bit bloated when you're used to something around 120MB. I think LE would be a much better and more focussed base for them.