Kerbal Space Program

You beat me to posting this one.

I also think we should have a turboshaft generator added, preferably with both mode for "closed cycle" (using oxidizer) and "open cycle" using intake air. Which basically turns fuel directly into electricity and heat, like a fuel cell but with far higher output and lower efficiency and more heat generation. These could be used as power-plants for player's big power hungry mechs.

However, placing an adjustable generator on the standard ones would be good as well, especially if they could do something a little more fancy, by actually making the EC generated based on RPM and the amount of torque you reduce your main drive by when the generator is functioning. A max output slider determines how much torque can be diverted to the generator.