I think it'd be cool if players could set up some sort of radio tower and hook it up to an album jukebox and broadcast songs throughout a large area. There could be a few different frequencies to broadcast on and other players could then use the radio to tune in to the nearest tower operating on their selected frequency to hear what's playing.

id second this, it would be great to have that, I haven't been able to find a single mod that supports this yet for 1.20.1 and above

Make the frequencies work like Create's frequencies, where you set it to two items.

I actually thought this was that the radio was for. You naming the portal radio, placing it on top of an album jukebox and other people being able to see it on theirs and tune in, but it wasn't the case :(