You are obviously a young guy. I am not. It is a recognized fact that young men feel invincible and that as you get older you get more cautious. You have shown some caution by deciding to start on a 250. I ask you to at least consider you are still underestimating the risks involved here. If you seriously consider all the risks and press ahead with your plans then I sincerely wish you all the best (however the little matter of insurance might get in your way)
I was also concerned by your motives for wanting to do stunts and ride the cool bike. It shouts “ego” and there is nothing more dangerous than ego when you are on a bike. Even this safety conscious old git nearly drove head long into a concrete barrier the first time someone complemented me at traffic lights. I took off fast and nearly ended my riding career 2 weeks after starting. If you put yourself in a group of your peers on a race tuned bike, will you have the self control to keep yourself safe? Not many of us would.
Be safe, have fun and be riding for many years.