Awesome work! As far as "too bright colors"... pfffft. If you want the look of a five-hundred year old map, yeah, they would've faded some. But if your map was made "in 1505" (or whatever the calendar of these realms says) and "today's date" is 1510, then the colors are more reasonable. Just as you chose them, I'm sure the master mapmaker who created this would've chosen nice distinct colors if he had them available. If the place isn't Earth, then who's to say the locals don't have access to nice vivid tints? You haven't cracked / burnt / aged the edges of your 'parchment', so to me it's a "new" map, and wholly believable.

The amount of detail seems to indicate the cartographer has pretty good geographical knowledge... but as we've seen, mappers have always been loath to leave space blank, and always claimed intimate knowledge that Just Didn't Exist. With that in mind, and getting into a 1500-ish mindset, there's details on here that get a free pass, which on a modern map would bring out, for instance, the River Police. Caveat - I am NOT a duly deputized River Officer, nor do I play one on TV. Really, even presuming the master who drew this knew river-flow patterns, all three main dividing-river instances might be deltas, especially the nice marshy one at the border of yellow/pink. The northern one's divergent streams are cased like coastline, so maybe those are two big sealevel islands instead of delta-lands. Casing the two passages leading inland from the east coast of NE "Redland" leads me to figure they're sea-level too, making that an awesome harbor instead of a questionable lake - is that what you had in mind there? Same only smaller on the east coast of NE quadrant Green - whether island at river's mouth or delta <shrug> doesn't matter. It's beautiful and no doubt admirably meets the needs of mariners.

Country name / city name balance ... again, not bad, unless it doesn't match what YOU wanted :-). If there's only 14 domains in this part of the world, and everybody (or everybody in the map audience) knows them by their banners, maybe the names don't matter much. Maybe in these realms, the nation name changes with every ruler, or every administration, whereas the flags have remained the same for millenia. <shrug> It's your story to tell! One possibility off the top of my head to both distinguish between and emphasize labels as desired is to use a bit different font for each. The eye can pick different messages out of a mass of text that way - all-caps spaced out for the nations, leaving cites tight 'crabbed' writing, that sort of thing.

As 'art' to appreciate I really like the totally nonLatin font. It emphasizes that We're Not In Kansas Any More. If your purpose shifts to using it for a book or a game, then a font that folks can easily pronounce would be a help - no matter if the pronunciation isn't what the locals would use. I once drove around Wales for a weekend with my boss the navigator calling out town names from the map and me recognizing them on road signs... no doubt in strings of sounds that would have left locals ROFL.

Have I said I like this a lot? I like this a lot. :-)