Please hint about the changes! I have my own ideas, but perhaps they are too ambitious to contemplate... or perhaps not!
Because a different IA for each game (with a choice of possible) would be amazing. The amount of replayability would be...astounding! Imagine each game being different from the last, not knowing how the enemy would attack, when and through what route!
If someone had the knowledge and the time, the amount of improvements to this game is limitless. For example,a way of making the tyical strategy of massing all forces in Xajorkith and leaving the whole of Midnight to the wolves a not so good idea...
Dreaming is free, but I believe the key to inmmense replayability does not lie in better graphics, but a more challenging IA. But of course that's a hard task and perhaps goes beyond your intentions... or perhaps not! After all, Mike programmed an acceptable IA 20 years ago in a Spectrum, nothing you computer geniuses can't improve, surely!