Sounds like a fun campaign!
I for one really like these maps. They are informative and very nicely done. I think you might want to consider making your muddy river texture a bit smaller.But other than that , Very Nice
Kingdom Of Shendenflar Campaign Setting (WIP)
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Even if I am correct, I would still advise you to follow your heart. This whole Cartographers Guild thing, it seems to me, is more about passion and skill and learning new techniques than it is about definitions and rules.
I really like this too. The style is original, albeit it can look a little syntetic someplaces, but it's very nice work altogheter.
If I where you I would probably try to find a more realistic grass texture, especially on the two first pieces. That is if there is not a thought behind that symetric look.