Freeciv ought to have more advanced governments. Three categories: Politics, Economics and Culture. You choose one from each category, and all combinations are legal (Planned Anarchy focusing on Conquest may be odd, but no impossibility). Government bonuses increase over time, making it less and less advantageous to switch governments to suit the situation and rewarding successful long-term planning. The bonuses increase in 'steps' occuring every 3^N turns (ie in turns 3, 9, 27, 81, 243 and 729). (Thanks to redguts on the forums for inspiring this idea.)