The one detail of my sheet that I think is most important to mention immediately is the Mottem Expanse.

Caerulmoste is a massive drainage basin adjacent to a number of estuaries and salt marshes by the ocean - meaning lots of brackish water converging to the lowest point, called Lake Tunis. Tunis then empties out from Caerulmoste into a subterranean network of caverns winding all around throughout the mainland.

Meaning there is a network of underground saltwater rivers/streams that can potentially be used for trade and shipping. Use at your own convenience, or not (it is easy to say there are no caverns connected to the network within your nation).

A number of canals in Caerulmoste connect Lake Tunis and subsequently the Expanse to the ocean - leaving it (for the moment at least) the only way to get between the sea and the expanse by boat.