If the boat came with a set of sails, I guess you are stuck with whatever sail area they offer, but the good news is that the Spray will make an excellent motorsailor anyway, and junk rig is the absolute perfect rig for motorsailing. I've done a lot of it on my 24 foot, 5 tonne Tom Thumb design, Arion, and the combination is brilliant. Also, off the wind, the Spray is surprisingly easily driven, and the junk rig powerful and effective, so you should have no problems sailing anywhere from 70 degrees off the wind to a broad reach. I have no experience with sailing on a dead run with schooner rigs so will let others advise you on that (there are several diverse opinions on the best tactic there). If you measure your sails, it will provide a reference point for JRA members to advise you on mast, yard and batten specifications.