After a bit of consulting with my aesthetic director, she decided the best looking flooring option was additional battens added between the existing ones. A piece of plywood added over the battens was not attractive and not adding battens made it unclear to anyone that would get in the boat whether to step on a batten or on the hull plywood.
The 6 additional battens were cut and edges routered on the top side. Then with some pencil mark-ups on fitting to the floor, a stationary belt sander made quick work of getting them to fit to the floor. The creative use of clamps as spreaders and some other contraptions allowed the battens to be pushed tight to the floor while the thickened epoxy cured. I could only do 2 or 3 at a time due to limited number of clamps that could be made into spreaders. The floor looks a bit like flattened organ foot pedals without the black keys.