>... the scan itself was way too dark. When I > turned up the brightness on the scan it revealed all kinds of missing details (like > the bug's legs and the astronaut's face). I'd hate to have to redo it from scratch > but I'm not sure what else I can do.
Found a Space Panic bezel high res scan on Arcadeartwork.org . Not sure if it is the same source as the one you used; this scan also is very dark and original bezel quite scratched.
After investing significant time this is the fixed and cleaned up result. Astronaut face and alien bug legs are now visible.
Does anybody know if the dark background (space) is just solid color or includes stars ? If they are not stars I'll remove all those background white spots.