This is drifting off topic. I was mostly just asking whether a boat designed not to weathercock or leecock was inherently inefficient, and how much of a difference it makes.
But,
1. I'm assuming I would pay someone to build me a boat, since I can't build it myself.
2. I
am trying to learn from personal experience with other boats.
I've had a lot of boats over the years, since the early 1980s. The Caribou is a pretty nice boat (thinner than most commercial boats, fairly light, though the Kevlar version was lighter than my fiberglass boat, fairly low profile) - for someone about 80-100 pounds heavier than me. For my weight, I lose 7 or 8' of waterline length, so it effectively is a short boat, though the wind and higher waves have leverage against the whole length. And it (and my old SOF too) sometimes gets into a pitch /wave resonance situation, where it wastes a lot of energy pitching forwards and back, generating a lot of splashes. That means under some conditions it virtually comes to a stop, and can also be hard to control when paddling into oncoming shorebreak. (If I remember right, the problematical height was about 2.5' - 3'. Above and below that height, the resonance disappeared.) That probably wouldn't happen for someone in the right weight range. I could add 80-100 pounds of ballast - but I suspect that would make it pretty inefficient. Ballast is no substitute for body size & muscle mass.
Race boats can be very light and efficient, and often have full length waterlines. I haven't played with them enough to give them a fair shake. But I'm afraid they handle so differently, that I would have trouble adapting. As I said, in my brief trials, I found using the rudder hard (though I admit that might have been inexperience), and my reflexes were a bit slow to keep them level. I am very used to leaned turns, and that wasn't practical in those boats. Plus I was warned that efficiency at race speeds is different from efficiency at lower speeds. A few people in my clubs use racing boats - but they tend to paddle solo, or only with each other. They often have different boats for different weather conditions, and they train a lot. There is no way I could keep up with them under any conditions. I won't try.
Most of the club members on group trips only use commercially made fiberglass so called "high performance kayaks" - roughly 21-23" wide x 17'-20' long. The Caribou is in that range but is lighter than most (I may remember this wrong; I think it is about 21.75" x 17'8" and 43 or 44 lbs), and I believe would mostly have been fine if I was heavier. Most of them are Greenland style, because that is what tends to be commercial available. So most of their boats don't really have that long a waterline. And aren't super-efficient. But they generally pick boats designed for their weight range. I didn't understand how big a deal that was when I bought it. Plus I bought used to be cheap, which limited what I could find. A few of them have built their own, mostly SOF.
I did fairly well when I used the SOF, which was 19" wide x 19' long, though I lost even more of the waterline length (the builder was heavier than me; he had full waterline length), because it was supposedly designed to roll competitively, not for speed, and by someone a fair bit heavier than me - maybe 200-220 lbs?? (For him, the cockpit just barely cleared the surface. And it wouldn't have if even a little water got in.) But it's no longer in good enough shape to be safe. I think, based on that experience, a little narrower but otherwise similar boat which had a longer length waterline and a bit more volume would do well. (I also found that the little round cockpit made re-enter and rolls - the only practical way to re-enter it from the water - difficult. E.g., I never managed to put the spray skirt on while underwater, so I had to pump it out during re-enter and roll practice. Fortunately it was extremely easy to roll, so I never actually needed that at sea. Also, because it was so low volume, my legs had to be straight, and I couldn't get a forward bend.) But those modifications to its design are basically what I am looking for.
I think some of the DIY boats at
Yostwerks Kayak Building Manuals - Homebuilt kayaks by Thomas Yost (MIRROR SITE) http://yostwerks.org/
would work fairly well for me, if scaled down a bit for my size and weight. I haven't tried one, but they are close to what I am looking for. Except I don't want the tiny round cockpit, I need more space above the knees, and I don't want black. So, with the same mods, might some of the Cape Falcon boats. I assume those are relatively minor design changes in terms of performance.
3. 16" x 16' is very narrow and a little short by sea kayak standards. But I have tried someone else's SOF boat that was that size, and liked it as far as I could tell. If it had a full length waterline, it would effectively be longer than the boats I have used.
4. I like the SOF idea because they are light (mine was 30 lbs) - but I'm told a lightly built composite boat could be at least as light.
