traction at top end

May want to consider a wider wing, maybe a Haase or Spitzer profile. An older wing may not have as efficient of a profile. Newer profiles produce more downforce with less drag. Also a carbon wing will make the car more stable as you have less weight hanging up and behind the CG.

As a comparison, most TAD's are 60-65" wide. Make sure you don't go over 999 square inches or you will need a fuel car wing stand.

 

Looking closely at your rear wing there is a possibility that the wicker bill that is so upright from the wing is actually hurting the downforce. Since the wing is actually upsidedown compared to an aircraft wing the wickerbill should be at a more gently angle like that of wing flaps. Yours is so upright it is spoiling the airflow over the wing and just maybe making less downforce. It maybe would be better to remove the wickerbill and add more down tilt on the wing. It is too bad you don’t have a rear suspension that we could actually measure downforce.

 

A wicker bill by design is mean to be at 90 degrees to be functional. The area between the wing surface and the top of the wicker creates a vortex roughly the diameter of the wicker bill height that is rotating in a circle in that area if you can imagine. So at speed, the air is not hitting the 90, but ramping over the vortex. It effectively changes the profile of the wing to be more aggressive.

Wickers are more commonly used in spoiler setups with no profile opposed to airfoil/wing set ups. They are a great tool to add downforce and are pretty clean airflow wise. A pretty smart aero engineer from the Indy car world said wickers produce no more downforce and only drag above 1.5".

Most of the time when you have a wing, you just put more angle in it. They were trying to maximize what they had. I'm not an aero engineer, but at some point the wing may be reaching so much angle it may get into stall. There's definitely more advanced profiles out there that get you more downforce.

I wouldn't be concerned with the front wings unless you went to a dual element set up. Kicking the headers up would definitely help as well.