Hello
I think you could give more "life" to the towns and villages, I mean, walking on the streets and roads is too boring, you see few NPCs going to nowhere, and you only need to go there for talking to the village elder, the guild master or the prison...
So the idea is let the player play with the town/village, like a real lord, for example:
-When the player goes along the streets of his/her town with his/her bodyguard, the people aproach to the player, and depending on the reputation with the place, they acclaim you, or they repudiate you, or he could have options like say something to the peasants, or drop money, or simple give the order to the bodyguard to push away the people.
-Give the possibility to repair buildings, or upgrade parts of the town/village, and see the results by your own.
-Criers on the streets, slave's markets, etc
-Let the player put some guards at the villages, and burn the buildings in the raids
In conclusion, make from the towns and villages something useful in the campaign, and at the same time, let player have more fun, more roleplaying options, etc
Also, you could add to the multiplayer the mods -Persistent world- and -CRPG-
Why?
Because you can kill in battles and sieges, but with CRPG, you have an objetive, upgrade your character as you like, leveling and making money in the battles, so it will be nicer than -oh my god, i start all the battles with a ****ty armor, when I make money, I choose good gear and i get killed, I lose all-,
Persistent world, its one of the best mods in all warband, it let the player play in a roleplay enviroment without tons of effort, roleplay with players is much better than with NPCs
if few modders did those mods with time and donations, why don't you?