As I mentioned previously, I have no intension of contributing to this design process but because you seem to be stalling out and I’d like to see what you as a group will come up with, I’d like to suggest some refinements to the process you’re following. While its fun to play with hull shapes etc., at this stage it’s a waste of time. I recommended the following process.

1. Compile a list of all the equipment to go on the boat including its weight (if known).
2. Draw a layout (plan view) of the boat showing all the equipment etc. (at this stage you’ll need to discuss and decide on a first guess location of the beams and and settle on a “standard” system for halyards etc.)
3. Draw a preliminary sail plan.
4. Make the assumption that your hull isn’t contributing to lateral resistance and determine size and placement of foils. When doing this locate the foils for the 2up option. If you place the foils for the 1up option you’ll end up with lee helm if sailing 2 up, however, the extra weather helm from having no jib if foils are placed for 2up can be offset with rudder angle.
5. Generate a weight estimate including an LCG (longitudinal Centre of gravity) by combining your equipment list with the data from the drawings. You’ll need to decide here on ideal (2up) crew weight and where you would like the 2 crew to be located going up wind (also check where a single sailer will end up to keep the same overall LCG). For your first pass through the process assume that the hull’s centre of gravity is at midships (this will be refined later).
6. Having done all this, now you can start playing with hull shapes. Things to consider: Location of LCB (longitudinal centre of buoyancy)
Location of LCF (longitudinal centre of flotation) the point the hull pivots around when changing trim.
Prismatic coefficient (how much buoyancy is in the ends below water lines).
Desired transom height (above or below water etc)
How the LCB and trim move as you transition from two hulls to one

7. Design the hull structure.
8. Calculate hull weight.
9. Go back to 1. and replace best guesses with new data.
10. Repeat 1-9 until nothing changes each time you do a loop or you run out of time and have to start building.