I'm looking forward to seeing what Stardock's vision is for this aspect of the game and I hope that we the community can help shape that vision into something that's fun. tid242 mentioned above that the current system is slated for an overhaul, so I'll write some general thoughts but mention something specific about the civilization ideology 'disc' that's in the OP first.
The upgrade that's highlighted is called 'Opportunity' and the description states that:
'Equality drags the least valuable forward while holding the most exceptional back. We should celebrate our leaders, not restrain them.'
I think there's a chance that the player may misunderstand this description. It would be clearer if the description read:
'Equality of outcome drags the least valuable forward while holding the most exceptional back. We should celebrate our leaders, not restrain them.'
Speaking more generally now, I mentioned The Political Machine, another Stardock game in a different thread and wondered how it might influence this aspect of GalCiv 4. There's potential to create a really deep and interesting political, diplomatic and espionage system here. For example, if the player wanted to take the authoritarian path then there would be a number of choices that they'd have to make and challenges that they would need to overcome. If they wanted to take the consent of the governed path then they would need to make different choices and have to overcome different challenges. Depending on the path the player chose this would involve elections and/or espionage and/or bribes and/or assassination etc.
Also, I enjoyed the civics options in Civ 4 that admiralWillyWilber mentioned. Perhaps we could iterate on that system?
I realise however that all of this might be too much for the base game. Maybe a possibility as an expansion?
There's potential to create some interesting and fun asymmetrical gameplay here. There could be a non humanoid species that's governed by a hive mind and thus internal politics is not an issue for it. It has drones that carry out its will and these drones have no will of their own. However, this hive mind could still have an ideology, and it's 'ideology tree' would be one that's only shared with other hive mind species.
Maybe there could be a species that's incapable of being ideological? Different options could be available to them that aren't available to other species?