Well, that makes a little more sense to me. My impression would be that you are actually dealing with two separate issues, initial stability and low rocker. At the dimensions you list, that is a pretty narrow boat, so any shift in the weight above the water line will be felt dramatically. At that length, without a good bit of rocker, you're hull speed is probably going to take a hit.

My suspicion is still that adding to the sheer will improve the volume at the top, but will do nothing to change the boat below the waterline which is where your issues probably stem from. In fact it will probably make the boat more unstable as you are raising the weight even further over your center of gravity. In my mind, adding to the sheer would only help you if the back deck was below the water line.

Glad to hear that you are a traditionalist regarding paddles. This is probably a silly question given your level of experience, but have you tried a sliding stroke when you need to power up?

Eric M.