Hey, I have been working with a group for a large scale campaign similar to what you guys have been talking about. Mine is on a much larger scale though in the scopes of a Total War game. http://prezi.com/99kfvnhhle3t/?utm_campaign=share&utm_medium=copy&rc=ex0share

This is the link to the galactic map. I also have a spreadsheet that keeps track of all fleets, planets and resources. Owning a whole system gives bonus credits. The Empire starts off with more planets and fleets but also much larger upkeep. The Rebels have more flexible and are able to quickly take the outer rim planets. Different planets give different bonuses and resources. The red lines are the ways the systems connect. Let me know if you are interested in hearing or seeing more.