front deck on river hawk/gheenoe....plywood vs plascore

Well I finished the patch on the keel of my boat and it turned out great.  Now I am going to start on the front deck in place of the bench seat.  I have already cut out the front bench.  I was planning on just using plywood and sealing it with epoxy and a layer of fiberglass.  My question is would it be easier to fiberglass the deck in with polyester and fiberglass mat or will it be fine to use the epoxy and cloth.  I have enough of both so that really isn't a factor.  Also, can I get away with 1/4 in plywood to cut down on weight or should I get something thicker.  I thought about putting supports under the deck to help support weight, and I am chopping up the foam from the bench and placing it under the deck.  I am going to mount a cooler to it, and occasionally have someone riding up there and fishing from there. 

***I read a little about plascore. Does anyone know what the difference in weight for it is vs plywood? If I could save weight it would help since my boat is the 13' model, but for the price difference I don't know if it is worth it.

 

Thanks for pointing out that link Brett.