I've had a handling issue for most of this year. When accelerating and decelerating the car would pull to the right and to the left and when braking it would pull left. I got stuck with the idea it was the rear wheel not being in line with the chassis. After measuring the alignment of the rear wheel I found it was off by about .029"; not bad.
I then looked at the left front brake and found that the caliper bracket was not square to the rotor and that the caliper was not sliding well on it's mounting bolts. There is the problem; a dragging brake pad. This too would make the car pull each way when giving it gas and letting off and when braking. Sure enough, new pads, caliper seals, shims on the bracket and reaming the slide holes fixed it all. It now drives straight all the time.
Now I'll go back and play with toe out and tire pressures some more and see what happens. Probably nothing but I think it's worth a look.