Toe is important.
Wht is your toe at ride height? It should be about 1/8" in. toe out will make it squirrely
Bumpsteer is also very important. You need toe OUT on bump, toe in will make the car squirrly and like to wander
Wide Tires can cause tramlining, where the tires try to follow the ruts in the road. i have 255 50 R17's on my vette that tramline like crazy. No cure for that except for fixing the road.