I think this whole thread shows the problem with UU's. Many of the UU's became part of that Civ IRL because of terrain, resources, or both. For example, the english unit is the man 'o war, but the english only had a strong navy because they are an island race. The russians have cossacks because they had a plentiful supply of horses.
I think what i'm saying is, the UU's would have been better allocated once the world has been built, according to what terrain or resources were around, rather than just which civ you pick at the start. It's going to be very annoying if you pick the romans and cant get iron without selling your soul to the only other civ who has it