Well if you ask me the best gov't would be Democracy, but the disadvantage is that it doesn't support your army, you pay about 1 gold per unit, but pollution is reduced quite a bit and can be completely eliminated when you get in the final age, but if you want to stomp the enemy, set Scientific research at 90% and happyness at 10%. I mean that's my opinion because im usually in the final age when the others are just completing the second age, then thats when i throw nukes, F-15s (Americans), stealth Bomers, stealth fighters, and Modern Armor. but if you ask me gold has nothing to do with war, WAR IS DESTROYING YOUR ENEMY!!! But if you want keep research at about where you gain a little money. Just what i do and i kill everything.