If the current est. length of 18' 7" is correct, then either the front hatch/rear cargo area, or both, will have to be reduced in size.
IMHO, reconfiguring the area behind the cockpit is the best way to maximize storage space. I'd replace the cargo and stern hatch areas with a bubbled (egg-shaped) aerodynamic hatch behind the seat running to the stern. It'd look really cool--like a race car with the forward end rounded off at shoulder heigth to form a firm backrest. The hatch sides would extend the gunwales up to the hatch cover. The hatch cover would start near the highest, widest point, have an opening big enough for large cooler, then taper down in heigth & width to a rounded end near the stern. The totally removable lid would be latched down (twice at the top end, twice along each side, and once at aft end). Its heigth, rounded shape, and downward slant would not only be cool, it would be the best design to shed water quickly, provide dry storage, and be easy to load. One large, covered, storage space is better than 2 smaller ones. It provides more utility and versatility, and eliminates loading gear through a small hatch opening that's so far aft there's not much room for anything anyway. Also, if the forward end of the new hatch incorporated/attached to the x-bar it would strengthen rigidity in all directions from that point.
The Rudder Control Arms, and rudder line tubes, should be outside the hull for easy access and adjustment--maybe clipped to an accessory rail at cockpit heigth.
Lots to consider/overcome, but a great, sexy looking, functional feature that's sure to sell boats--and that's what its all about. It would certainly sell me!!!
Thanks for listening.