Carlo,
I do like your tires, and agree with your statements about them and traction.
Years ago, I made similar discoveries.
I used to sell Chen Shin tires to the segway community. I believe that MadSegs used a set of these tires at the first MAMS and did very well in all venues.
A friend of mine called these tires I was selling as KETTS (Karl's Extra Traction Tires.) He called the ones on the left as Super Ketts.
I use the ones on the right as my standard tire, and run them all the time.
Currently, on my i2, I run the KETTs tread pattern, but in a slightly oversized tire. It is only 1 inch bigger (about 2.5 cm) but it gives me a bit more speed, and does not take away enough torque.
Have fun. Next time I plan a trip to Italy, I will surely look you up, and invite you to do the same if you come to the northeast part of the USA. (Boston area)
Have fun. Glide more.