Hey PvK, I had a cool idea for proportions the other night, although I don't know how much work it would involve:
How about adding a "Hive community" racial trait for insectoid races? Races which choose this (The Xi-Chung and Taera for example) would get access to a set of cities which are slightly cheaper (hence quicker to build) than the regular "colonial development" ones. Maybe they could have enhanced organics output, too.
If there are none in the image mod already I'm sure someone could come up with some really cool looking "insect-hive city" pics. If it could be made so that their homeworlds were full of giant hives (equivalent to cultural centres), that would look so classy when you conquered them
Whaddya think?