If you could be any enemy in Halo 3, who would it be? I would be a Golden Elite with a plasma sword.
The Elite aren't your enemies in Halo 3, they're your allies.
If you were talking about the previous Halo games then I'd also want to be an Elite but from Halo 3 I guess I'd want to be a Brute Chieftain with a Gravity Hammer and a Fuel Rod Cannon.