Richard Ferguson wrote:

30 inches or more wide.

That's really wide to the point of not even being a kayak any longer. I
cannot imagine a 30" wide boat that's unstable regardless of the weight
placed in/on it. Also, I have yet to see a boat that wide that couldn't
handle at least 300 pounds, regardless of what the manufacturer's weight
rating is. Even little 10' x 27" - 3" puddle boats can handle a large
load and are all rated to at least 225#.