Just an idea for the Void Gate: I'd love it if the Void Gate were bottomless, as in new creatures kept being added, preferrably without us publicly knowing what all was in there. If it could be balanced as far as stats go by a small group of moderators-who themselves would each only know a portion of the critters the void gate could summon up-then you'd never really know *what* you were going to get. This would also be a fine place to stick "easter eggs" if the Devs got involved

You could even have void artifacts-occasionally the voidgate could spit out a magic item or even a spell that noone's ever heard of before. Ofcourse, airbourne astral diseases that turn your citizens and troops into headless bloodfreaks as per crossbreeding are also possible...
P.S. I'm going to try to mod voidgate into early age, quite possibly a handful of voidgate sites, and then have some independent starspawn types, kind of to represent an alien landing (Thinking Chariots of the Gods here). Any suggestions for implementation would be welcome