So, to summarize: 1) You want to stop weathercocking, 2) You don't want a permanent skeg.

My suggestion would therefore be a retractable skeg--a very elegant solution that allows for fine-tuning depending on the strength and angle of the wind; and no lateral resistance at all when fully retracted.

A rudder should work, too, but then there are issues of sliding footpegs, extra wind resistance caused by an un-deployed rudder blade sticking up, the mechanism getting in the way of rescues, etc.

Retro-fitting a retractable skeg sounds complicated, but is probably doable. Some argue that it takes up storage space, but unless you have some sort of multi-week expedition planned, most sea kayaks have a ton of space, compared to a backpack.

Has anyone actually retro-fitted a retractable skeg? CLC has a simple method, but it requires cutting a slot in the top of the deck, which kind of ruins the look of a nice stripper. I would be inclined to pre-assemble the entire skeg-box with skeg and control wire, and add a thin carbon-fiber flange around the bottom perimeter.

Then cut a slot in the hull, add thickened epoxy to the flange, and insert the whole assembly--this should end up waterproof, and reasonably strong. For extra strength, do your best to run a fillet around the internal box/hull junction. Kind of tricky working from the rear hatch, but be creative!