Would an extra 2" of tread width help?

Unless you are trying to dead hook the car I wouldn’t add 2 inches more of tire. It takes a ton of power to drive those big assed tires.

IMO you need to spend some time looking at why your chassis doesn’t hook at 2 particular tracks. Maybe they require a different shock setting, or a different rpm on the 2 step.

Id look for ways to tune around 2 questionable tracks long before I bought bigger tires.