It would be cool to have an option for longer queues in Gauntlet to get more players in each game. Queues are currently really fast, which is good, but most games end up being against mostly AI as a consequence of those fast queues.
Maybe a vs. AI mode (this is essentially how a random queue ends up now, with 1 or 2 other players occasionally), and a mode that requires 4 or 6 or even 8 players to be matched before a game starts.