Thank you all for the replies, think the one with the Lego leg extensions would be my favourite! I will discuss this more with the boatyard guys where she is moored. I would stand in the hatch but then I can't see over the boat, the perils of being a little height challenged.
I really like the idea of the variable positions and maybe having two as suggested by ditchcrawler. At least there is a solution out there it seems
Oh and just to clarify, it was bought second hand and I didn't really notice how how the tiller was on the test run but after 6 hours on the tiller I did.