Gerrymandering is much more favorable in a FPTP system of elections than other types of elections. Winner takes all really incentives doing whatever it takes to keep winning.

Instead of your quite complex idea of segmentation, entities should simply move to a slightly more complex election system than FPTP, but which has reduced incentive for gerrymandering. For example, systems that give parties some seats based on the percentage of votes they get in the whole country/province etc.