First of all I won't be doing any of this stuff, so it's easy for me to pontificate
So in no particular order:
1. Exploration: nothing beats having to explore an unknown world. The bigger the better.
2. Story line: well, a good story line, with plenty of twists and turns, and loads of subtle puzzles actually beats having to explore an unknown world.
3. Avoid the E.E. "doc" Smith Syndrom: if you ever read that man's brand of SF, you need no explanation. Otherwise, think EV/EVO: ever more powerful enemies countered by ever more powerful ships (armor/weapons in this game). It should be brains rather than brawns
4. If there was a way to strip a player from some/all his Experience/assets/money and then move him to another continent, you could force him to beat the game more than once, so to speak.
I'll come up with more, as soon as send this in, of course
Alain
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