We will be using Mutants & Masterminds 2nd Edition as the rules set for the game. The Power Level for the game will be set to PL8. The characters are from a time before the war that changed the planet, and they have access to high technology that is still functional. However, they do not have access to super powers unless they are part of a device and can be explained through reasonable science. At the start of the game the characters will not have power or abilities, but as the game progresses this will change. I intend to introduce these changes as part of the story, so I will not have the players build these abilities or powers into the characters at creation. Instead, I want each player to brainstorm 10 characteristics that they think would be a fun addition to the game and that they would like to see in their character. During the course of the game I will ask for random d10 rolls, and I will begin revealing the emergence of an ability from a random table that I will build from this list for each character.
Note that I WILL expect the characters to do maintenance on their equipment, even Devices, and as such I strongly recommend having appropriate skills and equipment. All Devices will have to have flaws limiting durability and it must be possible to lose the Device.
Basically think of this as a cross between Fallout and Rifts to get an idea of flavor.