I like the idea of Automatic Show so I thought to add a few of my own ideas that can be added to expand on this:

Individualized Show:

• add an individualized Show composed per user out of individual trailers/video segments. The individualization would be based on the user selection criteria such as
  
  • pre-selected tags (standard Steam tags),
    
  • user's areas of interest (Action, RPG, etc.)
    
  • AI recommendations ('since you liked... you might like...')

Multi-show Offering:

• Show options based on the standard Steam categories (top selling/upcoming/etc.), "curator choice", etc.

In-video Functionality:

• video/video-segment/trailer length
  
• 'skip to next' (the next segment/game-trailer)
  
• click on video to go to the store
  
• add Settings section or right-click menu for more functionality (enable opening store in a separate tab/pause video on opening another tab/etc.)

All this is based on the premise that instead of one full-length video, each video is created out of independant video segments/trailers. If this is executed properly, there is also a few ways that Steam can use this to create opportunities for itself, but I'm sure they can figure that out on their own.