If I could change one thing... I would completely delete the map and start again. I would make each house one massive system only with several sectors with resemblance to the existing systems. The systems would have inter-system jumpholes to speed up travel between sectors, and each system would be treated as a complete solar system with a central sun. Each of the main systems would be linked by series of smaller sectors such as the independant/border worlds we have. Better to have a few players scattered across a few maps than a few players scattered across heaps.
If only it weren't so much work, if only the software would support it Dx