maybe, one sever can host a cyber war, that lasts days. this way everybody can play.
lets say you've played an hour in a cyber war, you've gained a specific rank, and you don't want to lose it. you can have the sever remember you until the war ends, this way, i can play the next day without losing my rank, letting me keep my earned credits on that game.
however, when a war ends, lets say it took eight days for nod to win, all the records(saved statistics) would be deleted, and every body has to work their way up the ranks again, this way a player wouldn't be at the highest rank forever.
next, the cyber war is like an enormous battlefield striped in to three or four parts (all joined together in a line) that forms a battle front, a player can see all the information on his field of battle (location of players, controlled areas...), however he can only see the percentage of land taken by his faction on the other fields.
the battlefields separate field or front's would consist of three bases, one is yours, one is your enemy, and one is neutral. basically, it's a rush to control the center base. the center base however, only has a barracks and a refinery. and you cannot re-spawn at the center base. your own base would have all the structures, and one automated defense. this would give a fair advantage to both sides, because this would make sure you can't keep on attacking with heavy armor, you would have to make a long journey to get to the enemy's base.
and finally, to end the game, either a specific time runs out or all the bases are taken.
to end the war, a time limit is needed. and to judge the winning faction is by seeing which side has controlled the most land or who has taken all the land.
after this war ends, a new one would begin, a war in another section of the world (lets say you've taken mexico, next battling on the border line of USA, then through several states and to claim total victory, destroy the gdi HQ, or temple of nod (kind of like the last mission on renegade).
after destroying either of them, all the players are then ejected out of the war. then a new war would begin, and all of the players would rejoin.
if you like to change or build on this idea, feel free to do so.