Hi, e_e. It's pretty effective just like it is. Mild improvements..... I'd wonder if the rivers might be more clear if you backed their sources off a few more pixels from the hills? The river network is pretty plausible, but after staring at it a while I figured out what bugs me - the "every hill begets a river" vibe makes it look almost like the only place rivers run is the flatlands. In the west you have more watercourses among hills, but I wonder if in the east you could improve the impression by implying some valleys as well as hilly areas. Or maybe not forcing every single stream to come from a hill - it'd be OK if some arose in such mildly raised terrain that it didn't justify hill symbols.
If your Imperial Cartographic Standards call for focus on each Province exclusively, fine, but ignoring the lands to the east so thoroughly keeps making me want to see the Scriba River as a coastline instead of a watercourse. Just one or two tributaries coming in from the east, or a road crossing it, or a town to the east would mitigate that optical illusion.
Have you tried it without the drop shadow on the labels? It does kind of make them stand out - I assume your goal - but it simultaneously lowers their contrast, which makes them slightly harder to read. <stares at it a bit more> AHA. That's what seems odd - those nice shaded hills have a light source opposite that of the drop shadows. If the drop shadows are even necessary, maybe they'd work better illuminated from the NE than from the NW?
Anyway - nice work; I like what you have going.