use random or preset groups of your unlocked units in QuickPlay
In QuickPlay you currently only have a preset group to use. After playing the game and unlocking units you should be able to use them in QuickPlay. You could have either your current group like in Multiplayer, or a random selection of units (either same for both players, or completely random for both). You could even have "sets" that get unlocked if you've bought the right types (like an sorcery set, a flying set, or a mounted unit set). Give quick play a bit more variety.