I'm another 3 inches taller SesameCrunch, and a LOT heavier I suspect, at over 250 lbs. I could futz with the riding position to improve it, but I suspect nothing I do will really make the Mini viable for me AND all my luggage. I've been using it exclusively because of the fact that it fits in the bag; without that factor, there is no reason not to use on of my 20" bikes, and sourcing a decent bag for one of those is probably easier and cheaper than making extensive changes to the Mini.
The final nail in the coffin of this decision is that I totally unexpectedly swapped a nearly 40 year old bus, which I long ago converted into a motor home, for the motorcycle below! I now need to liberate some room in my garage (I need to get rid of about 4 of my 20+ bikes), and also to raise some money for equipment and training for my bike license! I got the Mini originally as a demonstrater, and since Downtube no longer make them, I don't have the need for it in that role any more. Therefore, I'm going to replace the broken spokes, and put my Mini up for sale. I will still be looking for an alternative bag for my IXFS, but I think the likelihood of me having £250 for a trailer in the near future is small.....