They should make a playlist similar to Breakout, but you can revive each other. Almost like Gears of War-ish.
that would be cool, maybe with less health?
or RTCW.
It will never happen though.
A guy can dream.
If you got enough Spartans to reply it could happen.
They do have a revive mechanic thanks to campaign, so it could happen.
Trials of Osiris
Oh, wait, wrong game 
I think it may come if the demand is gigantic.