I think it'd be a good idea to have a Rumble match with your clan or a Fireteam of 6. I understand the balance needed so people don't abuse the ability to pad their stats or inflate their crucible scores, but if it was a purely social mode that didn't allow experience or crucible marks to be earned, it could have its uses. It would allow groups to find load outs that work together, test weapons and armor skills against others, allow fun, stress free competition between friends and more. You can display kills and deaths and such, but nothing would be gained. This would even allow game video to be used and created ala the Red vs Blue team from Halo. I think it would be a win/win.