Hi...
You can try with
Long wheelbase on the front that makes the car easier in corner entry.
Harder differentials' oils expecially on the front. Most of people run with a set of 150.000 (or higher) on the front and 60.000 (or 80.000). Harder oil on the front should make the car easier to drive in fast chicanes.
You have 600cSt oil in the shocks but how many holes opened in? Try with a 1 or 2 holes opened on the front.
And... you forget the downstop setting. So before to touch anything try to set the rear downstop value to 5 or 6 and you will feel that the car is very very stable when you are under braking.
Try and let us know hos is the car