Roku should consider creating a generalised internet radio streaming app, with an ability to input details of any internet radio stream along with a library of popular streams from major broadcasters. Precedent: similar to the Roku media player app.
The radio app could have a screen layout similar to the Roku home screen with a space for adverts on the right hand side. Roku could sell that advert space for revenue.
If not an channel app, maybe extending the current home screen to have a radio menu with the ability to add shortcuts to popular stations
There's an app called MyTuner which streams internet radio; there may be others. Roku did not create it, but it does work on the Roku
Yeah, I know and have that and several others.
All are limited compared to the wide range of stations that most DNLA streaming devices can pull in, especially those that link to one of the major radio streaming directory services.
And the user interface of most of the current apps is not great.