Great mod SSAllen!

You're lucky I don't know how to mod! Yet. lol
I'd definitely make one like this one with extra features. Guardsmen, enough to keep danger at bay while our collector jingles all the way to your bank depot(s).
So:
Guards to secure treasury and collector, where both guards and collector get a fixed wage.
Treasury hold where you keep all your money. Guarded of course by your most trusted men.
All nations (all 5) should have them to keep a balance, plus raids from anyone just like caravans.
almost forgot ...all this for v 1.xx of course.
Kudos!