Ezio has taken control of the kitchen, only providing sustenance to those who bring goods to trade with. The pantry and freezers are the most desired location in the entire house, nearly everyone seeking out the salty and sweet snacks.
Altair has used his location in the living room as the perfect spot to bombard anyone trying to get into the kitchen with a sea of pillows. No one can get to the kitchens anymore without first paying homage to him.
Edward, Ade, and Mary Read have control over the various bedrooms, attacking anyone who tries to use the bathroom in the hallway, which means no one can use the bathroom on the second floor without first offering up things they desire.
Jacob and Evie have control of the staircase, defending against both the upper floor and the second floor. People from upstairs can only get through if they have some sort of offering and people downstairs have to provide amenities like food and drinks.
Haytham, Shay, Lee have control over the den. They spend most of their time relaxing, enjoying the minor stash of wine and cognac that they had horded before the whole pillow war broke out. Haytham mostly uses this time to catch up on his reading, of course. Shay runs a messenger network, helping different groups peacefully contact one another.
Arno and Elise are in control of the cellar/basement, providing people upstairs with alcohol. Because Edward needs his fix and eventually the Templars ran out. Ezio, of course, requires some for his latest recipe, offering up a plate in exchange for the expensive wine.
Connor, Achilles, and Aveline have the attic and every rooftop, attacking anyone who tries to sneak out of the house from above. The attic also has a strange supply of extra blankets and pillows that the other floors end up trading for.
Desmond, Shaun, and Rebecca took control of the family room and all of the technology inside (TV, Computer, phone chargers). They set up a 'no violence' zone where everyone must relinquish their pillows before entering. Shaun secretly trades a charging cord for yogurts from the kitchen.