Good? Evil? Hah! Double hah! Neutral is the best. Those free terraformed tiles are just WAY too awesome. You gain the power of three levels of technology in one, plus you gain access to a beautiful extra few trade routes. AND you have an added advantage when you invade the worlds anyone who ISN'T neutral! Good and Evil might offer extra defenses or weapons, but you still have to research those. What amounts to free tech? Absolutely awesome!

Not that Evil is bad. I've played the Korx enough to know that Evil is profitable [which fits them, don't you think?]...but honestly, getting Soil Enhancement, Habitat Improvement, and Terraforming for "free" [no need to research them, thus tech doesn't get as expensive as if you did research them!] is just something that can't be beat when one's in doubt of what to choose.