I came from ErsatzTV which was IMO more complex than it needed to be but it has some powerful features in it's version of virtual channels.
Ability to control how many episodes of each show played. For example I have a channel I made for my wife that plays a mix of hour long episodes and 30 min episodes. I'd love for the flexibility to play 2 30 min episodes and 1 hour long.
Also the ability to better control the order of the shows on the channel. Example I'd like to play maybe 8 classic sitcom shows and then 2 dramas. Or perhaps pair some things back to back like Show A immediately followed by it's spinoff Show B.
Finally I know it's corny but my wife really loved the custom watermark I could embed over the feed every few minutes on ErsatzTV. Really gave it that real TV channel feel.