I like the reactor idea and think it could be expanded more into the story/plot of things. As I do recall, it's humans linking into Robots to harness energy and beam it back to earth.
Apply same concept to make it compete with other corps. Based on various rewards and/of buffs from the amount of energy being produced and sent back. Then something like a teleporter, similar to those big random beams in the sky could all have one per gamma and players need to get the energy to the transporter, so it opens it up for control and risk the supply by pvp. Almost similar to the original Transformers where the Decepticons used the transporter to Cybertron to send energon cubes back and then had the Autobots try to stop them.
Something along those lines, I think would be nice to see to actually give a purpose to be in Gamma other then to accumulate the most amount of minerals. Maybe even have some kind of smaller scale versions for Beta and Alpha to get new people started. Hell, could potentially change the random higher quality ore when mining be the Fuel source.