Lotsa great ideas ....

My own solution is to take out the entire starboard side rear berth cushion, and use the area for storage. Large low sided plastic bins can hold alot of stuff and stay locked in place by their rectangle shape and the remaining portside berth cushion. Life jackets, cockpit cushions, a mushroom anchor with rode in a 5-gallon bucket, spare Merc oil, funnel, flush ears, boat cleaning supplies, etc.

That "double" berth is not very useful anyway, as it is only accessible on the port side, and is impeded by the steering and motor cables, so it has become a single berth.
Then I gutted the built-in boxes of the galley face, (jigsaw and Dremel tool cuttoff wheels, and drum sander attachments ), leaving only the upper left one intact, and have a large contiguous area under there for storage of stuff in plastic storage bins with lids, with no obvious change to the external appearance.
Then all the rest of stuff, including a spare prop and tools, and spare parts and rope, portable water bilge pump, and some other stuff, is kept in soft tool-type bags, the kind that Lowes Depot sell of varying sizes, which are "modular" storage and fit into the odd shapes and curved spaces defined by the hull, under the forward settee, the portside couch, and next to the ballast vent cup.

Soft-sided bags waste alot less space than hard boxes, are more flexible in shape to fit into odd spaces, hold themselves from shifting around better, and are not a noisy as hard boxes clunking around.

More rarely needed things can go under the settee floor, ( if you have dry bilges )

Bar-floor mats, or plastic modular square mats make good hull liners inside the storage areas, to allow ventilation between the hull and your gear, and keep stuff dryer. They don't have to be arranged too carefully, just hold themselves in place by the confines of the spaces anyway.
note the two soft bags, as described, for holding tools, parts, etc.
This pile of stuff sitting on the cockpit seat, pretty much like it is arranged in the photo, all fits inside the galley now, after the gutting of the galley-face boxes, as shown in the pics.
