This is an expansion on the idea of scheduled Streams which are part of the Roadmap. Idea would be to have a calendar part of the interface (I'd suggest a three tabbed interface Stream/VoDs/Calendar but there are many possibilities) which shows a calendar in which the streamer can enter dates for streams.
As mentioned in the schedule suggestion E-Mail reminders would be an option.
Another helpful tool would be to show a timezone-independent countdown, when clicked on an event. Especially english channels tend to have a rather international viewership.
I would really love for something like this. It could be built into offline screens or something. Since we don't have custom images we could have our schedule and a countdown till the next scheduled time! Or if we do get the offline images customization at some point we could move it above the video if nobody is hosting or somewhere where it could be seen.