Well, if your going to drive if offroad on a dirt track, I would put some nice offroad tires on it from pro line they have many good dirt tires, and you should definitely consider some aluminum parts and a faster motor for offroad I think.
For on road or carpet racing, well your gonna need some new tires, maybe lighter parts, and if you are carpet racing, very soft suspension. If you put clips on or stiff springs you won't be able to turn well on an indoor track with your xxx-t, as with any car inside.
If you really are just fooling around in your yard with it, then this car should already be enough for you, the only thing you could do more for just subtle fooling around like this is maybe put lighter or durable parts on it, tires, and maybe like a 19 spec motor. My friend has a trinity chameleon in his rustler and it's actually really fast and can almost run with my T4 lol not really but o well. Just dial down your suspension, have your motor fast and the fun comes standard in my opinion with that. But with a losi car, there isn't much needed, these are quality cars.