I really like Vimu and bought it, best AndroidTV player atm.
What i really miss as Anime user is the ability to quickly switch the audio track and subtitle track via remote.
The latest Jellyfin client has a button remap options for just that, so if Vimu could add such a feature this would be great.
What i want is the ability to remap my unused (forward/rewind/play-pause) on my shield remote.
Than ultimately the most advanced solution is fully automatic audio/subtitle selection based on advanced settings.
In mpv you can use
mpv-sub-select script and set mpv to "alang=ja,jp,jpn,en,eng" to get this done.
In LAV filters on windows you can setup advanced selection as described
here.
Would be nice to have something similar, maybe just allow multiple audio track languages that can be sorted in a list window and do something similar for subtitle tracks?