Hi Richard,
I would take a good look at your mainsail and speak to a sailmaker. I suspect that a ten year old in-mast furled sail with no battens is not going to give you much performance. Years ago I had a similar setup and the sailmaker (UK sails) made me a new sail with vertical battens that furled inside the mast. The new sail was bigger because the battens gave it an almost normal roach. Performance was much improved. Worth a conversation.
Good luck,
Paul
The membership association for owners of Dufour Yachts