looks good man
i built one last winter - here it is in its undresed state -
i went for fully enclosed wheel - made it easier hanging lights / plate on the back, no need for a mudguard etc etc...
i just used a scooter leading link front end and ut it down - makes for a very cheal suspension system on there that works wonderfull
what are you doing for the hitch? i eventually just got a huge UJ, welded a tube on a drawbar i made up, and the UJ just slots over it and a pin drops through it to lock it in place - really simple but effective
and like you say - the single wheel trailers tow great
i think theres deffinately a market for a cheaper option - its the towbar thing that needs tacklind though as far as i see it - a lot of people dont want an ugly lump on the back of the bike when not towing so something tidy would have to be thought up
this one is worth looking at too for a manufacturer of them - nice simple design
http://oddlegtrailers.co.uk/index.html
good luck with it if you do end up producing some of them
