Are you planning on more bashing or racing? If racing, you have a lot to do because they are not the best for that at all. But work on the suspension, tires, and brushless would be a start.
its going to be used for racing. i know have to set up the truck for my track. but I've heard people talking about running their battery below the chassis and a few other things. the class we run you have to use brushed to keep everything close.