Would an extra 2" of tread width help?

Racing for consistency is tough like a chess game. Long and calculated. If you don't care to tune to conditions go bigger IMO.

On the other hand racing heads up is like an old west gun fight in front of a saloon, in comparison. Cars are pushed harder vs. track conditions round after round and like all competition the stakes get perceivabley higher as the night goes on. If you end up drawing a pistol againt your knife it's time to turn it up past your comfort zone and get ready to drive a little more than usual next pass.

Not all races are bracket races so consider other events you might take in that class cars by tire size. Very cool car and pics!