In my current version I left Chaos Marauders as Planar Gate Summons and replaced Minotaurs with Colubrae. My Colubrae are like Champions +3 Poison strength + Mutated + Channeling I & II, allowing them to get Mage spells even though they are still melee units and don't get free promotions based on the mana you own. I thought Obsidian Gates made more sense for calling in these creature of Ceridwen.
I also made Chaos Marauders a Chaos II summon, who are summoned with the Rebel promotion. This both makes the unit AI controlled like Enraged and gives a chance of turning Barbarian like burning Blood. The unit itself gains 1 duration from combat and starts with Mutated.
I'm still having problems with my Guild of the Nine mercenary hiring Code, but I intend to make both Chaos Marauders and Colubrae potential hires for AV civs. (This fits the AV these of Deals that Kael described a long time ago.) Other civs would be limited to Axemen, Archers, Longbowmen, Champions, Rangers, Horsemen, Catapults, ect, with a random race and UU being chosen for each unitclass selected. Any unit bought this way starts with the Mercenary Promotion, which costs you 2 gold per battle (basically bounty hunter in reverse) and has a 1% chance of making the unit turn barbarian.