I have a coupe of ideas on how to make for a better monowheel tire. Try taking a LEGO Rock Raiders, Power Miners, DinoSquad/Dino 2010, Indiana Jones, Star Wars, Agents/Agents 2.0, Alpha Team, Arctic, Technic, Bionicle, or Creator set that has either the linked treads or the big plastic treads and form a circle with it or, better yet, take one of those Hailfire Droid sets and simply make a monowheel from one of those wheels on one of those vehicles. I hope that those ideas help you out with making a better monowheel in the future. I like the design and it is very professional. Also, like the other guy said, you do need some sort of braking system and/or way for it to stand on its own instead of tipping over on its side as improperly built monowheels tend to do all the time.
Quoting Space Pirate
Looks really sweet and I wonder how you got this great photographs... :) Looks really professional!
Thank you. I usually take photos of my models in the daylight, on big piece of white paper. You can see how they usually look before editing if you look at my RTT-21 transporter. Those pics were not edited, because there are white airtanks on the model, and they could just blend with the clear white background :)
Very cool. I like the color and the shape. I would love to see it in a modern urban setting. What happens if the driver has to stop quickly? I guess that's why he has a helmet. Could you add a kick stand or a stabilizer for when he has to park? I am also impressed by the use of the gray plate in the wheel. Very simple but also very cool. Attack!