Coffee in Paris is pretty damned bad. First, everything is espresso. If you want more, they make you an Americano. Very few places serve filter or drip coffee, and their efforts were not impressive. The espresso menu is also pretty limited: straight espresso, Americanos or lattes. No mochas or anything else. People are pretty friendly though, and there's a culture of a long, lingering visits and sitting, so it's not unusual to sit in a cafe for a long time.
Best coffee shops in Paris are owned by Australians. Coutume was a favorite. Excellent food too.
Telescope was started by an American but could never make it there when they are open so never tried them