Last night I was looking thru one of my old issues of Electronic Games Magazine and found an odd entry...
September 1982 "Video Gaming Meets pop Culture" issue: "Sometimes successful properties dance from one medium to another so quickly it becomes difficult to tell in which direction the inspiration actually flows. In a sequel to it's groundbreaking original, Atari's Superman II will pit the Man of Steel against the trio of Kryptonian escapees from the Phantom Zone: Zod, Ursa, and Non. Superman must first dispatch the super-powered enemies with deadly Kryptonite before returning them to the phantom zone."
Of all the times I have read my old EG issues, I never recalled seeing this before. I'm wondering if the original Superman can be hacked into something of this nature. Consider these changes. Obviously they are just ideas but considering all the great stuff people have done with Adventure over the years, maybe some of these could be do-able:
Superman begins by entering the crystal chamber instead of the phone booth and becomes Clark Kent. He remains Clark for most of the game.
The vilains are changed from Lex and the Henchmen to the three Kryptonians (a graphics/color hack)
The jail icon is changed to a flashing "phantom zone" portal. Its position in the city could be the Fortress of Solitude.
The city of Metropolis is graphically altered- just so it looks a little different(?)
Clark (who has given up his powers) must collect the three Kryptonite satellites and expose each villain to one long enough to weaken them. Perhaps each villain requires a specific color to add more challenge?
The villains are wrecking the town- the longer it takes you to get them the more they destroy?
Perhaps you must repair damage after they are captured?
Again, these are just ideas but it would be interesting to see what could be done with the original program.