Too bad I can't create maps((((
Added 7 minutes later
In the Norington Castle, there is no tavern, and it's enough to kill him to prevent the Castle from being an obstacle. I personally didn't spend any time on him. As for the border guards, it might be an oversight on my part, I won't deny that. And the absence of spells was done intentionally; the boats were placed in advance. And regarding the appearance of the Black Mamba, I thought it would be simple; making Uma Thurman's heroine with the face of an orc or goblin would be, at the very least, inhumane. And the presence of a shipyard in some city far from water doesn't affect the Walkthrough in any way. And I've already played your map and didn't find anything special in it. The plot could have been more diverse. Otherwise, all the enemies are the same, except for the Castles, and it gets boring quickly.
And regarding the boats - it's better to place them not one by one, but in groups - otherwise, someone might start summoning a boat nearby, and it will disappear...