classic firefight please?

spartan ops is nice , but its no firefight.

where you compete for a better score in a more arcade based enviroment.
infinite ammo/weapons of choice.
getting 70-90k score vs 30k> others.

i liked the smallish arenas that have tons of covenant filling the be based on reach firefight maps would awesome.
i would especially like to see it as a custom game that can be forged on.