The first thing I can notice is that the car has a tendency to oversteer.
This is not super great, although the default setups for MR cars tend to create this kind of situation.
To fix this, make the front sway bar and spring stiffer, so that instead of shooting up at the end, the line goes down.
This should boost your tameness and cornering abilities.
You could also run more camber on all corners, as well as switch to a stickier tire compound.
The other thing I would recommend is maybe switching to the smaller of the two modern supercar bodies. Since the engine you are using is quite small, it should fit easily and help reduce the weight a little. Ignore this if you are already using that body, can be hard to judge from a single picture.
As for the last tip, I would reccomend raising your engine's redline a little, as I wouldn't be surprised if you had a few hundred more RPMs of useful power after you current redline. You reliability is already fairly good so it shouldn't be much of an issue, and it might let you switch to 6 speed with no reduction in performance, while lowering both the weight and price of your car.