I made these banners to clearly indicate who's ruling a clearing. Of course this adds a little required effort from the players who should change the banner every time the person who's in control of the clearing changes, but it quickly becomes natural and it's very practical to always see who is ruling the clearing.
Plus, they're cool!

EDIT: so far I only made the alliance, the marquise, the eyre, the corvids and the duchy, because I don't have the other expansions yet, but if you want me to add the others please tell me the missing factions!