[RC-Monster Mike]

Most find mechanical braking is more trouble(and weight and complexity) than its worth. The center diff will naturally bias braking exactly as it does during acceleration(technically the exact opposite), so mechanical bias is somewhat redundant.
Many nitro converts think they need it(because in nitro, the center diff cannot be slowed directly, neccesitating mechanical brake and its inherent bias), but later learn that it usually isn't worth the trouble. If it was such an advantage, 1/10 electric would likely have adopted it years ago. Having said that, you are surely welcome to use mechanical brakes and form your own opinion -or perhaps try a hybrid setup(mechanical rear brakes and 3rd channel mixing esc brakes for bias control). The stock front brake linkage can be installed on the motor mount and will work just like it does normally.
The 2200Kv MMM is an excellent choice. Pinion selection will vary with input voltage and track conditions, but I usually shoot for high 30s in my truggy for calculated speed(about the same as the nitros and plenty fast for most tracks).