Mike, your criteria so far seem to be related to stability and the lack thereof. If you are looking for a particular design and not just a boat to build I'd suggest paddling a lot more so that other characteristics of handling that are important to you can be realized in a particular boat. So if you paddle a rental Sea Lion, you can ask "is is easier/harder to keep on course than the sea lion?" or if you paddle a Looksha 4 the same question. The idea is to get away from terms like good/bad/better without a comparison to work it against. I don't know those boats well enough, and there are folks here that do, but my encouragement is to get a boat that you are in the upper range of it's paddler weight, most of your learning and day paddling will be in an unladen kayak. Paddling around a kayak that can easily accomodate a 225lb paddler when you weigh 175lbs is paddling too much kayak around most of the time, especially when you want to take your more advanced skills out into wind and waves.