Here are a couple of other tips.
- If you are okay with cheese, go with Liberty as your policy tree. Try to get Pyramids (for the increased Worker speed). When you invade a developed neighbor, bring a few Workers with you. Your units can pillage tiles, and your Workers can then fix them again in one turn. Then you can Pillage again. Due to Pyramids + Liberty policies you can repair improvements in one turn so it is very efficient healing. Yes, its possibly an exploit, but it works well. Also, Denmark (a civ most people dog on) is excellent at this due to units being able to pillage without expending move points.
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