I think the fusion cells are good and welcome them. They may have the same fuel benefit vs cost as other sources but we can pack more in a tank, doubling our fuel capacity. Spare O2 presents an opportunity. Some have already been mentioned: E.g Fuel for some weapons, either as a staple or a requirement for firing them in space. It has been indicated by the devs that we can expect true water planets which will need a steady stream of O2. If we get pressurized structures then these may need alot of O2 to maintain. How about some sort of afterburner or thruster benefit. Lets farm nitrogen and make N2O. I'm not very knowledgeable when it comes to chemistry but there must be other things we can combine with O2 that could be incorporated into the game, and would add some new basic resources to the game.