I was looking at the Virgin Atlantic brochure and the sure do have cheaper holidays from LGW. So indeed more people must be taking the BHD - LGW - MCO.
As far as I'm aware the deal is direct between American Holidays as the tour operator and Virgin Atlantic offering the seats, with connecting FlyBE flights included. Some may also book indpendently direct with Virgin Holidays, but was told specifically that many travel agents are booking through American Holidays because of this deal they have in place. Thus taking away demand for the direct BFS SFB flights.
Also now that Thomas Cook have stopped long haul flights from BFS they might add more european destinations.
Love your optimism, but not so sure. Recently Thomas Cook have went from basing 2 season long A320's, to this year 1 A321 and peak season Smartwings 737, and so far next year is just the one based unit. Obviously this could change with booking demands, but currently no peak season Corfu, no peak Rhodes, no peak Fuerteventura, no peak Las Palmas.
Hopefully these will be introduced over the next few months, as initially for this year we had a peak season bmi. This was then pulled along with the destinations and extra capacity, only to be reintroduced months later but using Smartwings. Zakynthos, Paphos and Gerona also all recent casualties from Thomas Cook...