Some comments on plywood glassing:
1) 4 ounce 'glass is mondo overkill (Winder uses 6 ounce 'glass for his hulls). Use 2.3 ounce 'glass, sometimes called "crowsfoot", instead. It's specifically woven for clearcoating surfaces, and requires much less resin to wet out than 4 ounce, resulting in a lighter assembly.
2) The West System for clearcoat hardener is desirable, but not necessary if the final coating is UV stabilized. If you do use the West System for clearcoat hardener, I think that the mixing ratios are different (or is the the humid hardener that has different ratios?), and I know for sure that it must be applied when the humidity is low to prevent clouding. The main advantage is that the resulting epoxy is thinner and flows much easier than the usual 205 hardener.
3) The most efficient way I've seen to apply the 2.3 ounce glass is the following:
4) Don't even think of painting. Linear polyurethanes streak when using bristle brushes, and the solvents eat through foam brushes real quick. The fumes are really bad, and it kicks off before you have the time to complete the job. Instead, prep the hull to perfection and bring it to a car paint shop. Ask for three or four coats of clearcoat on the decks, and get whatever color you little heart desires for the hull. You can even ask them to apply a base coat and sand it to get a really smooth hull. Specify a two-part linear polyurethane (Dupont Imron or equivalent). These guys will mix the paint and spray on the four coats in less than a day. You get a super tough finish that doesn't even need to be sanded. When Rob Levy and I had our hulls done, the guy only charged us $300 each, including the paint. The last time I bought some Interthane Plus, it cost me almost $75/litre for the paint and the required solvent, and I only managed to paint the deck and cockpit of "Men in Black".
5) Glassing could be used to give some trapeze hook protection to the tankside tops, and maybe for some reinforcing around the mast partners.