I really can't understand playing as an Elite in multiplayer. Honestly, in Halo 3 only the worst played aS Elites. The players who typically, though admittedly not always, were too unskilled to keep up with other players on a level playing field. I'm sorry for offending everybody, but that's just the truth. The Elite character model had a number of unfair advantages, blatant handicaps, and altered the fairness of the game. It was NOT simply and aesthetic difference. The very hit-box of an elite is different than a Spartan.
Multiplayer should be a front based on giving all players an even field of opportunity and then letting player skill take over from there. Thats how multiplayer Halo was always designed to be, and the addition of Elites was a massive oversight of this idea by previous developer, Bungie.
While the argument can be made that the tendency of players who chose to play as Spartans tended to vastly surpass those playing as Elites, and so the playing field evened itself out anyway, it was still a largely unfair advantage.
Some of these unfair advantages are:
-The Elite head was far more difficult to hit from behind
-The Elite body was overly predominant over the model and the head was at an awkward position for multiplayer. The hit box for the head sat low on the model, and was less defined and more difficult to work around with accuracy weapons.
-It has been proven that there was at least one spot on the Elite model that was literally, or indeed very close to, invincible. As in dealing damage to that part of the model would do either no or very low damage. This area was one that was quite easy to hit for other players, so it was a bit of an issue.
Note that it was VERY common practice in Halo 3 to switch character models for the SWAT gametype to an Elite because it was know that the Elite was harder to score head shots on.
Also, Halo 3 Elites in multiplayer didn't make dimensional sense when compared to the Elites of the campaigns of other games. Notice how Elites are in fact a good bit bigger than Spartans. So Halo 3 Elites made no sense. This is probably a good bit of the reason why they have been left out of the recent games multiplayer-wise.
Sorry guys, its just a bad idea.