England because they're commercial, which means less corruption, and seafaring, so they can move out into overseas expansion faster, thus creating big empires over vast continents....or miniscule islands. I also like the MoW because it's a bit better than other ships at that time...and it's a pain to constantly lose friggates to galleons(I think that's how it goes) before Ironclads. THis way, I can control the seas if I want to.
I also like the Byzantines because the scientific trait helps with the libraries/universities and some of the bigger wonders. and the free tech and fun UU don't hurt
Finally, there is La France, the only civ with the "passive" traits(they don't have an effect directly on any one area, but one on everything within the city). I can have low corruption, great defensive UU at a good time, and it's a lot of fun with the metros...
Michael