It would be prudent for us to address the three general wind regimes with the open source design for sure. Light (0-7 knots), Medium (7-15 knots) and Heavy (15-25 knots).

It probably only affects the centreboards, rudders and hulls though, because the effectiveness of these items will change with the speed and heel of the boat, but the structures will have to withstand the highest loads anyway.

Are we designing for windward-leeward courses or other? A simple design aspect that will be affected by this decision will be the height of the bow. If shy/tight reaching much, I would want a fairly high and full bow to take the trimming moment from the sails, if doing windward leewards (hotdogs) we can get away with much less reserve volume in the bow. If designing for both, I would want to be on the conservative side of a full bow.

Speaking of bows, I have debated for a long time the effectiveness of wave piercing designs. With kite/spinnaker cats, the bow will rarely bury upwind, and will certainly not be succeptible to nose diving upwind. Downwind, the kite will lift the bows significantly. I think "wave piercers" are more effective at removing weight from the bow of the boat rather than actually piercing waves. Probably looking at a kilo or two on each hull, which is nothing to sneeze about all the way out at the end of the bow. Reducing weight at the extremities of the boat is an effective and proven way to improve boatspeed.

I'll admit that wave piercing may be effective on A-Class cats because they have such little hull depth and no kite to lift the bow downwind. But again, the weight reduction in the bow probably has more effect.