The toughest part of this is deciding what starts the fighting, and then, who is left without a partner. 5 vs 6 would be a good fight, and I can see 1 and 3 getting into it.
That leaves 3 girls watching four battling on the floor. 2, 4 and 7 look to be the same size, but will one abstain and look for a fight to finish before she steps in? So many possibilities. One thing for certain: those cute matching tops will see some wear and tear before it's over!