The bandit camp idea is nice. Although, I think it should be given a more general name because they are not always bandits.
Something that can be set up for a small clan to be as the Head-Quarters. Something that they can create (Perhaps give it a day or 2 to finish) Then enter and use as a defensive stand.
You can make it enter-able and such, although no trading nor population, the army would work the same way. Gold as well.
Could make for an interesting setup.
The only problem is the scenes. We may need to use the basic concept of what Fire and Sword has when you set up a "Wagon fort" of sorts, maybe a little more complex. Nonetheless this would be a fun idea I would support if we can find the scene creators to help out!
EDIT: This could also make Sieges look like real sieges on the strat map, rather then a bunch of dots surrounding a castle, you see a bunch of encampments. Create scout encampments as well as Patrol. A lot of possibilities.