We have play tested the empire variant but we made a couple of modifications. First of all, instead of doubling all the pieces, we have only 80 tokens, not 110 and only 8 ships. Also, instead of starting over at 1 for the trade cards for cities over 9, we start at the 3 level and continue up. Since most people don't get more than 12 cities, it means that these extra cities are actually useful. We originally doubled all the cards, but realised that was too many, so next time we will probably have 1.5 times the number for each commodity. If you exceed the limit on the commodity, you don't get extra points. So for instance, having 7 bronze gives you 150 + 6 = 156. This also allows you to use all the new calamities. The ideal scenario is 5 players using the whole civ map. It actually works quite well. Try it out!