Thanks for your insights.
Kneeling while rowing is awful, I'm good for about 5 minutes in that setup before I start swearing and have to stretch my legs.
I have an inflatable now, no wheels required as it carries easily on a shoulder between car and wharf and on fore deck when at sea. So many leaks and constant patching has me frustrated. I'd love a slightly smaller, lighter, rigid tender that could stow on deck and be easily lifted onto the car top roof rack for transport.
Might need to build something like the
http://www.plyboat.com/tweak.html or similar.
Let me know if you have a better solution please.
Cheers