I'd try changing the seat position first. I've got a solo set up to be trim with an 80-pound dog in front of me, and it works fine for the paddling we do.
One disadvantage is that you're not at the pivot point, and your maneuvering strokes will be different. But I'd rather deal with that than carry ballast and be even heavier.
It might make sense to get a second seat & set of hangers instead of trying to modify the originals. That way it's easy to swap back to the original configuration.
Touring Kayak Paddles
First Need Purifier
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