The formation of Highmarch was made due to a combination of people questioning why we had the territories in the north, and if Vix was destined to be some sort of super-conquering machine that would cover the continent, as well as the fact that all of the territorial gains drove the base tax line to like 5%. If our intention was to make it so we had a capital right on the front-lines, then the capital would definitely be in Akesh since it could hit everyone rather than Domus which is only 2 regions away from Vix's capital and tucked deeper in.
The Perdan situation was a wild-card Duke who wanted to reform Perdan, but chose to transfer the duchy to remove Perdan city from being the realm's capital so he can secede later and make new-perdania or something, but that's being handled ICly, but its clear from all the chaos going on with region transfers that this wasn't some elaborate plot to game the system.