Slash 4x4 Buggy 1717 6s

[RC-Monster Mike]

Looking good. Tires are just like you describe - the better traction they provide, the faster they wear out. Regarding front toe - zero degrees is pretty ideal. Generally speaking, toe-in generates better initial steering off power, but tends to push more coming out of the turn(on power). Toe-out is essentially the opposite, providing less initial steering entering off power, but much better steering on power. Of course many other things in the setup affect steering.
Rear toe-out is almost unheard of, as it generally created instability. Rear toe does create some scrub, but adds straight line stability(pretty important for high speed). If the rest of the setup is pretty rigid(minimal flex and play in the linkage, etc.), I like 1-2 degrees rear toe for high speed straight line work(3 degrees is the norm for off-road).