I like the CD Gulfstream. Mine is outfitted with a narrower glass seat. But the standard seat (or I think they may have a wide seat offered as well) is designed to handle a stockier paddler, and should offer some room for someone thicker in the hips and thighs. The deck height should also be good and comfortable for you . Most more recent designs seem to have followed that concept of getting rid of concave curvature in the hull. I think folks have found that when you push hull speed - sprint and race type stuff, any concave areas tend to be the areas where a lot of turbulence is introduced. The other thing that those concave curves can do is create stiffer tracking. At the time of the Gulfstream’s introduction, CD’s Solstice series employed that fine entry at the bow and stern that those concave curves can afford. P&H kayaks like the Sirius, Bahiya, and the stern of the Quest also had concave curvature. Since then, Current Designs redesigned the Solstice hulls to get rid of that, and loosen the hull some for maneuvering. P&H came out with the Cetus, and a big part of that design change was getting rid of the concave curvature in their previous fast cruisers, and a big part of the advertising there was maneuverability. In any case, the Gulfstream is a nicely efficient kayak for its length and rocker profile at a strong cruising pace.
The Gulfstream is considered nice and stable by experienced kayakers. It can feel somewhat wobbly right at first for someone who’s not used to sea kayaks. But it’s a quick one to grow into. I like that stability profile. Some kayaks can be too stiff in their primary stability, and believe it or not, it takes more coordination to smoothly handle your edging when it takes more to put and hold it on edge. I don’t like needing to use a notable effort to pull my kayak up on it’s edge. I want it to respond from just a shift in weight. Otherwise it can feel like you’re fighting it from both sides - trying not to let it go over, and trying not to let it fall back flat. I feel like that takes more coordination. The Gulfstream edges back and forth very easily, between a solid secondary stability you will feel as you edge it significantly over. So it has that sporty, responsive feeling, while still leaving you feeling secure within the bounds of secondary stability.
It’s a fun kayak for rough water and surfing. And it does everything with sea kayaking quite well, except for one thing. Maneuvering. She is a fun girl when it comes to maneuvering. The Gulfstream is actually pretty exceptional in the maneuvering department.
For extended excursions, you definitely want to be comfortable in the cockpit. No snug points just sitting in the seat relaxed. If she’s comfortable for you, it would be a great way to go. A lot of folks get caught up on the width of the kayak for a guy my size (fairly slender). But it performs, so I don’t fret the width. I’ve dismissed that concern with this kayak. For a stocky guy, you should definitely give one a whirl, as it was designed by someone shorter and stockier than I.