I'm sure they could make custom variations work! The game does seem tailored to it too. Just look at for example the gear choices the characters have, like Cassie with her drone, and Sonya with her.. well, drone. None of the variations they have feature that particular gear piece in a prominent fashion, which is evident of slapped together design where the guys doing "The eSports" aren't being directed by the guys doing the vision for the character, and compromises have to be made. I've said it lots of times before as well, the game is beautiful, plays great and is generally awesome, but it's plagued by unneccessary things like this, the Towers of Time being poorly balanced/designed, the lack of communication about the Krypt, online not counting towards Towers of Time goals etc. etc.
Seems like a lead designer who was supposed to have oversight over everything was sleeping a bit. Ed Boon?