My first map

[Anomis Twinklegaze]

That's well done. And the River Police have no problem with it :-). The relative heights of the northwest terrain are ambiguous, but the path that northern river takes is plausible. As far as how the width looks - you pretty much have to exaggerate river widths when your map is basically an orbital photo. If you stuck with pure 'photorealism' then like you say, they would be a pixel or less wide and pretty much disappear. It's a map, not a photo, so some symbology is fine :-).

And thanks for jumping right in with a map - that (and the fact it's shaping up into a nice one) is worth a bit of rep. Bravo!

I didn't even know there was a River Police.
Actually, I didn't chose the rivers' paths, they were generated automatically by wilbur and I only highlited them to be shown in the final map.
Thank you for the critique, though I didn't understand the last part (English is not my mother tongue, not even my second language).

Anomis