It takes almost 4mm to center the weight in the 1/12th motor pod.
Brian,
We've done some work on this and I think it will prove to be the right thing to do. There are those who don't think it is necessary, but in addition to the tire wear issue you mentioned we think the car feels better balanced on the track with a balanced motor pod. That being said, a car with an unbalanced pod doesn't exactly feel bad. But you have to ask, if you were designing a new 1/12th car from the ground up with the plan that it would only run brushless motors, would you center the weight of the motor or not? It makes sense to me that you would center it, just as it is basically centered with brushed motors in the current pods.
I've found that with Parma wheels you can easily center the weight in the pod and get the axle centered at full width, as long as we use a right side hub that has 1mm removed from the wheel flange (a lot easier to do than making a hub LOL) A better solution would be to have a narrower right hub, say 3mm narrower. CRC now makes one that they place in their brushless motor conversion kit for the GenX that is just that. That gives you room to adjust track width for tuning
As for the marketability aspect of such a product, I wouldn't take a guess, as I have proven numerous times that I am a poor judge of that
