I think your lack of grip may have been a combination of not enough weight and as with hatchet the screws holding the tread on being proud above the rubber, I don't think the tread was overly grippy to start with but it seems to wear down quite quickly. Can't wait to see your attempt at brushless drive tbough, mr mangle proved it's a viable system but the drive isn't the focus of the robot, with hardwired however you can really go all out with it