I think it would be great fun to add in asteroid belts, or patches within asteroid belts, which have extremely closely grouped asteroids. Close enough that the largest ships (Anaconda, Type 9, Cutter, Corvette, perhaps even the Type 7) can't navigate, but smaller ships such as the Sidewinder, Eagle, Viper, Condor and Imperial Fighter can pass through. This would allow areas of refuge for pilots able to enter such regions, and dodge any fire coming in from outside.