Some of the suggestions above have been absolute fantasy! Long haul routes from Bournemouth?!?! There isn't enough seats for this flight and another! Let alone the adequate gate! Could you imagine a full flight to Cancun boarding from Bournemouth!?
Ryanair will only do the popular sun routes, there is no market for Seville, Jerez etc. These are offered from Bristol, Stansted, Gatwick. No reason for a Bournemouth offering.
Easyjet probably will never come, I would of expected them to come with the new terminal but that didn't happen. They have a good offering from Gatwick and Bristol.
Monarch - very unlikely. Other than maybe a charter offering for the summer.
In my opinion, although this is very negative - try to keep Ryanair to do an all year round to the popular destinations service. But for this... I think for the winter they would need a smaller plane.