Played 3 times , here is the review
Unfortunately , Napoleon : total war doesnt add much to Empire total war .
In fact , I think it is less !
Napoleon's campaigns are the only new thing , they are great but you only get to play as Napoleon .
In the Coalition Campaign you play either as Britain , Prussia , Austria or Russia in addition to playing as France Through Napoleon's campaigns.
One of the downsides is that you cant play as other nations like the Ottoman empire or Spain .
Playing as Napoleon in the campaign is the hardest in my opinion and playing as Britain is the easiest .
The naval battles are - in my opinion- the best in the game with so many new ships with only 1 downside , you dont get to try your new ships in battle because by the time you have researched and owned one of the new ships , there are almost no enemy ships on the map !
Conclusion : If you havent played Empire : total war yet , I recommend that you play it instead of Napoleon : total war