I had made a suggestion in the PP beta forum before it was shut down. i say let the battlefields decide what powers control systems.
I would like to see conflict zones and instances that are created by PvP interactions on the spot. So players from each power could start battles themselves creating their own conflict zones, let this information be generated to the ticker tape on Galnet in realtime broadcasting in these areas so Cmdr's from all sides in those quadrants who were in range could then join in. Make warzones true warzones. Make the battles count. Have stations go to 'red alert battle stations' in these zones, where if your not aligned or allied or friendly with a station when station is at battle stations, then you are fired upon as a enemy and not allowed to enter.
Make wartime trade routes necessary to resupply these stations in order for them to operate. Stations can waver and even fall if supplies aren't delivered. Have traders have to 'jump the shark' in their trade runs for the chance at huge profits for supplying these wartime stations. Make it so wings of Cmdr's can also escort these traders if they want to, makeing nice profils for successful deliveries as well, while counter wings of Cmdr's try to interdict and disrupt these trade lanes, making large profits for destroying these traders, also making large war bond payments for doing so successfully. Miners could mine for materials needed for supplying the huge industrial war machines factories in the time of war, making huge profits as well for taking the risk of doing so in warzone areas. Miner's too would need Cmdr wing escorts in these hot zone areas. When stations weaken and fall in wartime systems then the winning power who inflicted the most damage in the conflict takes control of that system and it's stations if all fail there. It would also generate a whole lot more PvP action which I think would add to ED immensely. Let rank be decided in the Klingon way, the boldest and bravest excel and grow very wealthy doing so!
To me Cmdr's battling for systems would be a whole lot more fun then just making countless repetitive data deliveries for them. But that's just me speaking of course.
FD could design something along these lines for power play and make it a lot more interesting.
Edit: I think PvP incentive of making much larger profits, vs solo play, which if you chose to play solo these warzone areas they would then be invisible to you, so playing solo you could not participate in them.