RasPi as BT speaker/receiver for HiFi - PA config

I’m rebuilding my OSMC RasPi & hoping to have it as a more robust HTPC solution.

Works well/GREAT as my video server, but I’d like to be able to have is serve a more simple function, that of a bluetooth receiver.

I have a semi-decent speaker set plugged in, but I still prefer getting my audio via the TV (just does not sound right, a little too booming for others in house), and would like the speakers to play music coming from my mobile (& others @ home)

I’ve loaded the a2dp-app-osmc component & effectively does what’s needed as a PoC, playing audio via HDMI.

I need help configuring my video playback to happen via HDMI, but A2DP via audio-jack as well as the Spotify app/plugin (Airplay too, though I don’t use that; for guests).
Of course I need to ensure that DLNA would default to HDMI.

My PulseAudio-fu is weak (last had to dig into config YEARS ago), so short & sweet tweaks - possibly with TV-frontend and/ar ncurses tools - would be greatly appreciated.