Yes, the motor + esc from the frog will work just fine with the Ninja, I dont recomend any more motor in the Ninja as it always had diff problems with anything more then a stock motor.
A 3300 mah will give you more runtime then a 1500, I run LIPO's with all my vintage cars, thay are lighter so less stress and more speed
These fit in most vitage cars :
http://store.rcspeed.net/catalog/pro...roducts_id=329