This was brought up for years at the old Live365 especially in the old forums. A premium listing option for the top position in the genre page and /or station page screen capture on Live365 main page. ( see image. yes, I used my station ;)
It could also be a tick box option on the broadcaster page and automatically added to the monthly streaming charge. Untick the box at anytime during the month to not be charged for the next month.
If there was more than one premium listing, they could rotate on a fair algorithm depending on how many there were. Like a change every screen refresh. Not only does this add $$$ to the Live365 bank account, it allows lesser listened to stations get a chance for more exposure. Seems like a win/win for everyone.