Just tires and get out there. I also put on some “sport” bars and I will say that it did make a pretty noticeable improvement to turn-in response, but by no means is it a requirement. The stock bike (with some decent tires) will be a blast! Go for it!
Glad you had a great time! Feel free to talk to a control rider for tips. I think you were pitted next to Kevin, who is quite fast, and I think was control riding in that group. There are always opportunities for each of us to get faster. I would be happy to ride with you next time! (I stopped by to celebrate after riding a session with Kevin, and ride an S1000RR). You passed another rider going over the hill in turn 3 -- that is a place where a lot of people crash, so I would say to be careful. Otherwise, you are clearly running a solid pace for that bike, in that group!
Thanks for the advice! I was next to Kevin for this day, he was super helpful and mentioned the same thing about turn 3. Still learning the ropes but had a great time.