You know i have killed more covenant than i care to remember. I played Halo Reach firefight offline for hours on end on legendary. yet i only remember being an elite in halo 3 and in multiplayer on reach. But when do we get to be a grunt or hunter? without some kinda hack/mod? I realize that may not sound great to some but maybe the challenge of progressing thru a hole new style in order to rank up and unlock new classes of that grunt or brute. I think knocking someone senseless as a brute would be refreshing. I mean if you see it you can be type thing. maybe nothing but playing as the various species and factions in big i mean huge team battles to give new life to the whole war feel.Just imagine when 1 of those guys who is awesome as a spartan lights you up caps a perfect game by running circles around your dead body arms flailing the whole way like he is in terror instead of the stale old teabagging thing i mean most of us are guys thats kinda well…old
Heh, I made up a mock version of this years ago.
Imagine a game where you do get to play as any of the Covie races as well as any of the UNSC ranks (marines/ODSTs/Spartans).
Each class would have it’s pros and cons. I won’t go over the whole thing again, but here are some highlights of it:
Grunts, low health, but gets high points for killing. The tougher the enemy the more points.
Hunters high health but low points for killing. Since the Hunter would be at the top due to health and overall firepower, the points points decrease as the enemies get weaker. They move slow.
Classes that would be relatively equal would be:
Marines/Jackals
ODSTs/Skirmishers
Spartans/Elites
During a game, if you die you can choose a new class. However, you must stick with the same affiliation throughout the whole game. So if you choose a Covie class you play as a Covie the whole match.
Each class has specific loadouts and abilities.
For example:
Brutes-sub classes you can choose:
Brute minor - Weapons/can dual wield starts with Brute Plasma Rifle and Spiker - Ability - evade
Jumppack Brute - Weapon start with concussion rifle/Plasma Pistol (cannot dual wield) - Ability Jetpack
Brute Chieftan - weapon start with Gravity Hammer only. Can dual wield. Ability - Armor lock (yes I know, but for this class it makes sense.
When you choose a class, you can NOT pick up a new ability. You are stuck with it until you die.
So scoring variables are accounted for by class as well as what weapon you used for the kill. Lesser powered weapon nets higher points. Stronger class wields lower points.
I have this lined out for all Covie and Human classes. I could just as easily incorporate Flood and Prometheans into this too.
Hey there I totally agree with the idea to play as Covenant forces other than humans. I even made a post about a spin off like ODST that i imagined. The Protagonist in my Imagination is an Elite that fights back the Brute attacks on sanghelios and other planets After the Covenant war. If you like you can read through the ideas 
you sound like you are on almost the same page. i don’t really like to make 1 race have lower health than another really unless armor attributes actually mean more than just cosmetic appearance. mainly because of the idea of somethings you just don’t live thru like a sniper round thru the skull, jumping face first into a mortar from a tank cannon,etc. rather the races have different abilites in addition to the standard combat controls like runninr crouching shooting. for instance instead of an armor ability a species abilility or skill that in some way is superior to versions the others race may have and some have no version at all but a completely different set of abilities. i played a star wars battlefront game kinda along lines of both our ideas i believe but i am curious as to what we all could influence on this topic
like a massive battle type game that makes the game seem more intense. i am ready for days when you can get into battles with about 50-60 people involved and maybe make them historic epic battles from throughout the whole time line like halo wars did.