Any and all bikes can use help in the same areas, tires, suspension, engine (ecu flash), exhaust, brakes, wheels, grips, levers, rearsets, seats, frame/swingarm adjustments etc. Stock bikes are far faster than 99% of the riders. To get your bikes limit, it's all about you, not your machine.
Work on the part between the ears, that is where you get faster. Your bike is already faster than you are. The easier you make the bike to go faster, the bigger the gap between your brains and your bikes capabilities.
You really wanna learn to go fast on any bike you start flat tracking and learn how to handle a bike thats moving underneath you and make it go in the direction you want while it aint pointed that way.
Not sure why you would increase the viscosity of the fork oil. What is your weight and lap time at Fontana? Sounds like you are under-sprung.I didn't explain in my original post, but this was an instructional Academy, that also had prizes for the biggest lap time/consistency/smoothness improvement. I agree with you on the fact that the bike doesn't need much more speed. But for a $100, why not install grippier pegs for better bike ergonomics. $370 BREMBO 19 RCS Corsa Corta, what a difference in feeling and precise brake control. And finally changing the front fork oil to 10 W really helped with the front suspension. These are all well worth mods that help with bike control. Same goes with the $50 tank pad, for better tank grip.
I spent $2795 for instruction in this last Academy, fyi. So, trust me, I know the importance of it.
Not sure why you would increase the viscosity of the fork oil. What is your weight and lap time at Fontana? Sounds like you are under-sprung.