Character draft variant?

Heya guys
We're playing DT quite a lot, and I was wondering whether anyone has a draft variant for BO3 duel with only one collection? I can't quite come up with a good idea on how to make it good sport without allowing mirror matches since we've got only one of each box. The idea stuck with me of "pick 3 characters during draft, then ban one, play with the other two, first to win must change the character", but it's the 3 lineup choosing process that causes me some headache
tyvm for your suggestions