Custom Sandbox Mode
It would be great to have a custom sandbox mode where we could set the number of players/bots and other special rules. (like AI doesn't attack or AI has extra handicaps/buffs)
This would be great to have in the future, but for right now it would make learning characters so much easier. I'd love to load up a map with just me and an AI that doesn't attack, with the timer off so I can take the time to read and learn my character's abilities.