Group intra-realm duels

We already have an option to challenge a realm mate to a 1v1 duel, and the testing of the upcoming PvP event made me realize that it could be cool to allow groups to duel. As of right now very few people do this even though it can be quite fun, and a lot of support classes are left out of anything other than a novelty duel (clerics mace dueling or something). Currently both parties must be ungrouped to commence 1v1. Could there just be a check added to ensure both sides are in equally sized groups?

Would be fun to see allies fight it out or set groups from 1 realm going at each other. Just please don't add any sort of incentive or title to be gained. I think it'd be cool as just another option like the current system, not something people strive for.