My tastes are simple. I think all you really need is a Vanguard V-twin engine, vertical exhaust stack with flap valve on top, vertical intake stack with forward facing air scoop on top, twin rear vision mirrors, and a twist-grip throttle on wide motorcycle handlebars. I don't suppose I'd say no to self-propulsion with six-wheel skid steer, but that is getting a bit fancy. How about some grass skis for the operator? Or if you actually wanted to make it into a fun project rather than a show-pony, why not convert it into a Victa version of the Honda Odyssey ATV? I nearly bid on one once at a clearing sale, but as it turned out it went for quite a high price.