> I wonder if it would be welcomed in this project for others to pick a game schematic > and rebuild it electronically?
Of course! You're welcome to capture another schematic and/or a netlist. I've seen that gEDA has a long list of netlist export functions and am quite sure I could add my XML format to that. It'd require to recapture Pong and Space Race from the ExpressPCB schematics, but that shouldn't be all too hard.
It's just that when I tried various schematics editors that none seemed to be mature enough to do the job. I'll give gEDA a try now.