YD-40 design, please give me some advices

[Jiyu]

I want to design a luxury sailing yacht, but i can't continue, would you mind give me some advices which can make at least 4 people on transom together, in order to make enough space inside, so i have to reduce the deck place especially the outer space.

This is my main number
Displacement 8.1 tonne
Lwl 12.45m
Bwl 2.837m

thank you in advance

[marshmat]

Jiyu- is this a just-for-fun exercise to see how some ideas look, or are you planning to actually build it?