Try this idea:
15 players on each team (30 in one game)
Weapon Start:
UNSC:AR, Magnum
Covenant:Plasma rifle, Plasma Pistol
Everyone starts with 30 points
while waiting for game to start, players can either buy loadout weapons (will come back to this), base defenses, etc. . after game is full, a final 30 seconds to get stuff so last person to join gets a chance. When time starts, Huge door at front of base opens. Huge map, open territory. objective is to get to enemies base, go through it and destroy an objective, like a power core. Each player has a limit of 30 lives, each time they die they spawn back BEHIND the base, to stop being instantly killed by enemies attacking the base. When lives run out, players have the option to either leave the game or go into spectator mode, where they control a camera but cannot communicate with team mates who are alive. when you lose a life, you will go back to youre spawning area, and you have a 30 second respawn delay in which you can buy weapons, vehicles and base defences with the points you earn in your living time.)
POINTS:
1 point per kill
2 points per headshot kill
multikills:
normal points plus 1 point for each level of multikill (for example, a double kill would get you 2 points for the kills, plus 2 points for the double kill)
Points can be used during your respawn delay time.
WEAPONS:
DMR:10 points
Sniper rifle:20 points
Rockets: 30
n00b tube (yeah, i dont know its name): 50
You get the point (lol accidental pun :)
VEHICLES
Mongoose: 20
Warthog: 50
Scorpion:100
so on
BASE DEFENCES
Turret (max 5 per base):25 points
A.I. Marine/Grunt with AR/Plasma rifle (Max 5PB):50
Overshield layer for base objective (max of 3 layers at once):150
If bungie likes this idea then they can improve on it.