Not missing anything and agree improvements in lower arm motion are bigger net benefits. Delrin in the lower control arm will provide much greater benefit than it will in the strut arm.

Like you describe, braking should be lessening or done as steering input is added. I'd also say the initial stab at the brakes in corner entry creates more pitch than the gradual roll into throttle creates at corner exit. This is why I thought the firmer bushing on the back of the strut may create less change than on the front. But yes, this is fairly minor in the scheme of things.