This has been partially brought up, but I favored the idea of either:
1- The region is good/evil/hospitable/etc/whatever Toady puts in, based on the civilization you currently control. Currently that would be dwarves, but later should extend to humans, goblins, and those other, less awsome
elves. Later it may hypothetically extend to include player-made civs, too. But this should be a long term goal, not a "do this now, and do it right" kind of thing; that's notwhat I'm asking.
2- The region is good/evil/you get the idea, but only in a relativistic sense (Meaning no booze rains, unless the sphere is booze, or something). That way, a good bime is only
good if what you control is
good. Otherwise why wouldn't the good lands all be colonised? The elves (cannibalistic tree-lovers they are) are considered good somehow by the PTB. That's why they settle in good regions. Evil would try to kill everybody, Good would try to "help" everybody, Youth would prolong aging, remove life-caps, or not have them age at all. Death would kill you, Disease would make you sick, give infections, and have water stagnate naturally. Labor could make you're dwarves inspired to work more, better, and faster, with fewer breaks. Basically, it would do
http://tvtropes.org/pmwiki/pmwiki.php/Main/ExactlyWhatItSaysOnTheTin <that. This would, as it was stated, let players challenge, or relax, at their discretion. Some might be more open-ended in morality (Rebirth, Fate, Revelry, etc,
http://dwarffortresswiki.org/index.php/Sphere but would still be suited to some playstyle. Maybe Urist McGod would have a son, who when he dies becomes Urist McGod Jr. and carries his insanely game-breaking genes? Again, not saying this should be implemented right away.