I recently discovered some more data for helping determine your lay-up. MacNaughton Associates publishes a booklet describing a "Scantling" rule for what they call "Sheathed Strip Construction" or wood strips covered in fiberglass. "Scantlings" are recommended dimensions. You can order a copy of the booklet through the link below.

Incedentally, the rule suggests for a boat with 300# displacement that the strips be 0.25 inches thick and 6.14 ounces of glass be applied inside and out.