This is just what i have in my head for a new mode:

A mix of the Viking campaign were you raid the Samurai Fortress, Dominion and Skirmish.

2 Teams with 8 in each (16 players total). The attackers have certain entrypoints (like scaling the walls and breaking the gate open) and the defenders have some defensive weapons (but they should not be able to "aim" like in the campain but more like the "Arrow Storm" and "Catapult" feat) and ofcourse plenty of cannonfooder in the shape of captains and soldiers. And ofcourse the areas that is targeted should be like the features, large red circles that more or less signals "Death Aproaches". If the attackers captures a point, they gain a "spawn point" closer to the action and the defenders lose one in return. The defenders can recapture it if they repell the enemies before they can capture a point thats further in. So imagine 3 circles naming the inner one C and the outher one A, the attackers cant capture C without capturing B and the defenders cant recapture A without having B.

I have noticed that during the faction war, some have made it to the enemy stronghold with atleast 1 territory, but nothing special really happens other then that the faction that gets the enemies at their door pushes them back. So if this would get into the game, Either have it as a normal game mode like Dominion and the others or have it trigger at the factions strongholds when an enemy faction reaches it.

Ofcourse this would be a massive mode and would require time to both create and play, but if i would use a map as a measurement, the Sanctuary Bridge would be a lenght to it (refering to the spawn and area B) between the capture points and perhaps the areas A/C to area B for the spawn points (same map, to get into the fights) to give a measure of distance of the scale of the map. And for the width of it, I think the Sanctuary spawnpoints would be a great distance for atleast the walls to keep the attackers and defenders from more or less stay in one place. Just some suggestions i have and if someone else do have some ideas for a game mode, either post it on a new thread or post it here.