What I still haven't really understood whether the "new Embraer experience" will apply only to the E190 planes, or also to the E170s. Where by "experience" I mean the blocking of the neighbouring seats, new seats, WiFi...

It's not that all CDG flights are operated solely by E190; there are numerous flights operated by E170s from CDG. And often they get swapped freely from one to the other. In which case it would be pure luck whether one has a free neighbouring seat or not.