A classic shooter game with a more... in-depth multiplayer mode. Imagine if a match, instead of a 15-minute objective mode, instead was total war waged between three factions? Take Far Cry 3- imagine setting up a map in the editor where each faction had three outposts surrounding a main HQ, and players could basically do as they pleased? For instance, let's say you've got an island map where Blue Team starts on a very elevated area that's hard to reach by roads but can be done stealthily on foot, Red Team starts separated from the others by a large river and beaches, and Yellow Team has large expanses of flat grassland between it and the others.
The basic "attack plan" would be for Blue Team to make hang glider assaults, Red Team to make aquatic assaults, and Yellow Team to defend themselves on their large land expanses.
However, objectives appear that are much deeper. Pregame, teams can decide on base compositions that affect how matches play out- for example, let's say Red Team had a marijuana farm. This increases the total amount of money they have for munitions, but the other teams can then destroy the farm (say, with fire, or pesticides) and cause Red Team to lose money, giving them less choice in weapons. Alternatively, they could take a Weaponsmith setup, which would allow them to change the base guns available at the cost of space. They could set up either basic industries and buildings as well as Pirate-specific ones, just like the Islanders (blue) and Soldiers (Yellow).
You don't get classes until in a match, where you can choose from available weapons and attachments based on what you made in the pregame. Weapon choices fluctuate, and if your weapon isn't there anymore, it forces you to switch.
Money is also needed. Every time you die, your team loses money equal to what you spawn with. You could choose absolutely nothing and go in with a machete, which is a survive-and-steal strategy, or you can start heavy and outbid opponents on firepower. The choice is yours.
This in-depth experience blends MMOFPS, strategy, and survival. From building your faction and defending it to taking sidequest-like objectives, you reach the ultimate goal of overthrowing the enemy. Shorter games could use a points-based system, and the full one much like Risk- take everything and then you're done.
The main objective would be to take down the enemy HQ- the three outposts help in preventing this, however. Normally the outposts fall and then the HQ is left with a much harder job of defending itself, but stealthy players could attack and destroy the HQ before an outpost falls. In the case of outposts being the last remaining player spawn, players may still spawn but are severely limited in money, guns, and they aren't a player for score any longer. They can cause problems for who killed them for a short time, however.
Objectives will be shown in full. Have a flamethrower? Burn some farms. Doing small objectives will hurt enemies or help you, allowing you to gain an upper edge and destroy the enemy.
Sadly this would require server power not available for consoles and an internet connection of the gods, but having a "drop in drop out" system that allows players looking for a match to be thrown into existing ones where players have dropped out, and god forbid I even mention it but have AI-controlled psuedoplayers, could fix the inherent problem.
I want the holy grail so I can drink from the fountain of youth with it, then ride my pegasus into the sunset. Who said my goals were unobtainable? I never said UNICORN.