>>I plan to put the cruiser bit of PocketShip to the test, with planned sails in the Apostle Islands up here and then trailered south to the Bahamas by way of Florida. But as has been said, comfort and safety are important, so I thought one of the ways to get that on PS would be to build compartments under the soles in the cabin for things like water and provisions storage. It would work like the ballast lifts only more of them.
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Weight distribution in a boat this size is pretty important. You don't want to sail around down by the bow or down by the stern.
The ballast scheme was designed in anticipation of cruising stores in place. I bring this up because I've noticed that many PocketShips are being daysailed in "lightship" condition. Which is great; the boat is a brilliant daysailer. But probably somewhat under-ballasted without stores aboard. The first time I took mine cruising (out of Duxbury, MA), the addition of dunnage and supplies for my wife and I for a few days made a big difference in the boat's handling. I have advocated increasing the inside ballast in boats not carrying much gear below.
Anyway, start by filling the compartment under the mast. This counters the weight of the crew seated aft. (In theory. Try a trial loading at the dock and just see how she sits.) Small heavy things like canned food can be stowed beneath the floorboards, but there isn't all that much room down there. And keep in mind that the bilges might be wet. Drinking water should be distributed low in the boat, in small bottles.
I put sleeping bags, sleeping pads, and dunnage under the cockpit seats. That storage space is large and perfect for things that are bulky but not too heavy.
Visitors to my boat have noticed the nice zippered bag right under the companionway. Perfect for small items that you need to reach while under way. Given the time I'd add more bags like that around the cabin.