You can't limit torque by gearing or higher KV, any brushless system with sintered rotors, etc. is going to have monster torque (zero to top speed in 1.5 to 3 seconds, traction allowing). You're just going to put more strain on your setup if you do this. I know Novak offers some 'L' motors which are a bit tamer than their normal line, and some replacement rotors, but otherwise you just have to learn throttle discipline.