MV
You asked why I thought that the EXT-NCL BEE service would attract leisure travellers whilst the NCL-PLH AWW service does not seem to. I'd say marketing is the answer.
In Devon & Cornwall PLH is viewed more as a "businessman's airport" whilst EXT caters more for the leisure trade (mainly outbound until now). Maybe it's the business travel sector that AWW are aiming for? Flybe seem to have a marketing arrangement with some hotels in Exeter and Torquay. The TLH Leisure group in Torquay advertise on their website that you can book your Flybe ticket and hotel accomodation in one transaction. It seems to be working as the vast majority of GLA & EDI pax appear to be leisure travellers.
As for MAN...well, JEA and Eurodirect both operated the service and the sheds and Jetstreams always looked to be full. The Exeter business community has been asking for an EXT-MAN service but I'd have thought that to fill a Q400 that would also require a sizeable number of leisure travellers.
Which Paris airport? CDG offers the onward connections but I would have thought that ORY must have several vacant slots available!