Gramps: Turns out, lofting is quick and easy. Especially with smaller, simpler sails: each panel top is straight, and each panel's leading and trailing edge is a fixed slope. Bottom of each panel has a teensy curve to provide concavity to the sail. It's especially easy if you choose 54" Dacron -- only 4 panels and a bit!
Because it's winter & I'm bored, I plotted out a scale model based on the Sailcut numbers, then made a model boat to try it on. Graph paper, which isn't ideal sail material. Wind supplied by a fan.
And beam reach
Looks to me like the draft needs moving forward at the foot (which Sailcut can do), and should probably reduce the radius on the foot, too. Estimated cost for material is $185, not too bad (includes pre-made luff tape.) Sailrite kit is $285; cheapest ready-made I've seen is $325 (Sail Warehouse).
Now, what strength material should we use? This is a 100% jib, for a very windy location. Thinking 5.4 oz cruising cloth; are the High-Modulus Dacrons superior in shape or longevity? They cost about the same.