Lots of useful details and suggestions here. I think I've found a local dealer where we could try a Double Vision.
For comparison our Spirit II is 17' long and almost 36" wide. With only us in it, it will float in only a few inches of water (leaving the majority of canoe to blow around in the wind). That's nice on shallow rocky rivers, but on a lake it really wants an extra few hundred pounds in it. Short of some of the largest tandem sea kayaks I've seen, nearly every kayak I've looked at (SINK or SOT) has a smaller footprint in the water and is going to ride lower. The SOTs look like they'll have a higher profile above the water though, and put the people higher. The tandem we rented a while back was a pretty basic open top, like a Perception Prodigy tandem or something similar, but we flew past the canoes that were out on the lake thanks to the low profile.
I've thought about the Necky Manitou II before, but the Old Town Dirigo seems like a slightly roomier version of the same thing with some slightly nicer options. The front cockpit on the Necky looks pretty small. Old Town, Necky, and Ocean Kayak are all owned by the same company, I was under the impression that the Old Town and Necky kayaks are made at the same place but I could be wrong.
Also, I think you two are agreeing more than you realize in general, you're just getting tripped up on some design details -- there's alot of variety in canoe and kayak design. Enough to confuse me, that's why I'm here! But I'm learning. (Also, I'm a physicist, although fluid dynamics are not my strong point. In grad school they kept the naval engineers in the basement, I didn't go down there very often.)
The Kayak Wing
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