You didn't detail everything done to the car, so I'll mention several things that you can try, if not done yet, as you can afford it.

1) Poly or solid motor mounts, including a torque strap.

2) Poly trans mount.

3) Solid front leaf spring bushings.

4) Clamps on the front 1/2 leaf spring segments.

5) Frame connectors.

(The less "give" or "cush" there is in the mounts, suspension & frame, the faster it will react.)

6) Lighter throttle return springs, as long as you keep it safe.

7) Shorter front tires. (I prefer to keep the rear tire pressure at the optimum traction/footprint level.)
8) Periodically lightly sand any "glazing" off of the rear brake shoes. It can help hold better and bring the converter up a bit more.

9) Carb tuning. Experiment with the accelerator pump circuit for better response off the line. Squirters size & pump shot duration. Jet for mph and pump shot for 60'/330' times.

You may need to try different shock settings in the rear after making some changes. I run my Rancho's at 4 out of 5 (old versions) which would translate to 7 or 8 on the newer 9-way. I never cared for 90-10 style shocks or OEM because the lift too easy. You're going up instead of forward. I like adjustable shocks on the front (Viking or QA1) which have an external knob set between 2 & 4 out of 18(?). But it just depends how well your rear suspension works. You may need the more immediate weight transfer. Each car is different.

The can be a couple of hundredths difference in reactions between tracks and timing systems - track set up variations as well as the timing system brand itself!