Reverse engineering

I've been experimenting with different boards for awhile now.  There are a bunch in my garage.  They range from 7-10 foot.  I've found the shorter I go, the better it's working out.  I'm anxious to try out a 7' 4" board I picked up last week.   It's a bit thinner (2 3/4" thick) and a little bit narrower (20 1/2").  My intention is to find my favorite and copy it.  I think that building with cedar and balsa should keep the weight down.  The rails will probably be pine. Anyways, making a board that works as well as my foam ones is going to be a challenge.  I know it can be done and I'm looking forward to starting one in the next month or two.