I've thrown around the idea of a "campaign" of TDMs, basically the results of one battle dictating the next map. The loss of a certain battle can cripple the war effort of one of the teams, so, if one of the teams looses a main tank plant, then they will only have three battles worth of tanks. A "battle" being a week or so of the server for the TDM being hosted. If you loose a port, weapons could be downgraded as your own weapons are terrible compared to those that are imported. The point being, each battle is important, and can dictate the "outcome" of the pseudo-war.
In edition to the two main belligerents' armies, there are also sub factions, such as militant and resistance groups, who have there own doctrines, such as no defined classes.
The current idea I have is this;
A socialist state with a entirely war based economy, is at odds with a theocratic empire of the north.
The socialist state, the Union of Socialist Democratic Republics, or USDR which has the mastered the (un)holy trinity of the Military-Political-Industrial complex, is at odds with the zealous theocratic Northern Empire. Both nations are vastly different in military doctrines and resources.
As of now, the current doctrine of the USRD calls for a professional army, and a firepower/armor focus, as such their soldiers have slightly more health but are slightly slower. Their tanks have more health, but if there tank plant is attacked, they do not have as many reserves as the NE have. They are slightly better armed than the NE, but get slightly less time in a battle in which they are required to capture objectives, as they do not have the reserves.
The Northern Empire doctrine calls of a quantity over quality sort of doctrine, with a main focus on speed and quantity. While they do have worse guns, they have masses of human waves to overrun their enemies with. Their tactics are somewhat outdated, believing that defensive lines still have a purpose in warfare. Their infantry has slightly less health but many reserves. The loss of tens of thousands does not concern them as long as the incompetent commander behind them doesn't let it happen again.
As for server add-ons, Gcat's vehicles and default weapons pack are going to be used.
I would appreciate feedback to I may develop this idea further.