I am not going to use the standard "teak and holly" plywood for the new sole. Instead, I am going to make a varnished plank floor.
I'm working on giving the cabin more of an old-fashioned, classic wooden boat feel. I've been working on a few interior woodworking projects along those lines, including replacing a non-structural interior bulkhead with a frame and raised panel assembly.
Check out this cabin sole:
That's pretty much the look I'm going for.
That sole is simply varnished planks of solid wood, butted together. I will use Southern Yellow Pine, ripped into about 4-1/2" wide planks, resawed and thicknessed to 7/8". I will oil and varnish all surfaces, then screw them down to the new floor timbers. I will countersink the screws and plug the holes with black walnut plugs for a nice contrast.