Look carefully what the conditions are really like. Most inland lakes I know are very light & holey, and sailing a shortboard, even very wide, is a slogfest. Even when you think it's blowing, the lulls are more frequent than the gusts. So if the wind is often below 10-11 knots, a longer waterline and a daggerboard (Rio, Kona, etc.) will increase your time on the water many times.