I am french and I've lived abroad for years, never in the US. I am now in Australia and there is that coffee shop called Gloria Jeans. I don't know if it is american or not, but if you do something like that in France, it should work. All of my french friends/family, coffee drinker that I know have found this place and the coffees excellent. Personally, I do not like the coffees in Starbucks or the shop. It is too "american" for me.
If you do a coffee shop american style, but not too much, and with the right amount of french touch, you are a winner.