-Did you draw the lines of the deck elevation (profile) out full-size,

That sounds like a good idea, but no, I didn't (yet). I got the basis for this from Oliver's 12/22/12 message in this thread:
"I went with an ocean cockpit but raised each of the forms leading from about the front hatch to the coaming rim successively by 1/4" per Jay's suggestion (i.e., I cut the template at the midpoint (shearline) and added 1/4", then 1/2", then 3/4", then 1"). That gave me a nice fair curve on the deck, a little easier entry into the cockpit and a bit more room for my knees"

Re: keyhole - I do intend to build a keyhole style. That works fine in my Tern

Bill: Fortunately, the hull is nowhere near complete. In fact, I haven't mounted the forms on the strongback yet. I do have my Arctic Tern, with the cockpit I like, available. Unfortunately I had already glued the patterns to the plywood just before this thread was started (by James, 12/21/12). Modifying the forms now is not as easy as cutting paper. I'll have to cut the plywood forms, cut spacers (including replacing the blade kerf as well as the height addition respective to each form), and do a bunch of edge glueups.