Folding bike for commuting and touring
Some people do tour with Bromptons, so don't rule it out: Touring on a Brompton, Brompton cross country touring, The genius of Brompton touring, Brompton touring.

I don't know about France, but in the UK, not all trains allow large wheeled folders. If they do, something like a Dahon Espresso is a quick fold, but not very compact (folding handlebars help, and newer models have them as standard). The Dahon Cadenza is slightly less bulky, but slower to fold.

The Jetstream is 20" wheels, doesn't fold as small as some other small wheel Dahons, but would cope with some sorts of touring better because of the suspension compensating for small wheels to some extent.

If you ever want to take the bike on a bus, you will almost certainly need a small wheel folder.

Another possibility is a Riese und Müller Birdy. They do get seriously expensive, but fold nearly as small as a Brompton (compared with a large wheeled folder; if your main use is commuting with public transport, the Brompton fold is enough smaller and neater to matter). (There is now longer a Birdy model specifically named "Tour", but they are still used for touring.)

(Photo below from http://www.pbase.com/image/83944065 is an older model Birdy.)