if i were you i would get a good brushed motor for it. i would think a 15t would be nice.
maybe something like this
http://www3.towerhobbies.com/cgi-bin...?&I=LXJAJ4&P=7 or
http://www3.towerhobbies.com/cgi-bin...?&I=LXJAK2&P=7
depending on how good the batteries are you may want to get some new ones.
seeing as you just got into rc cars im not sure if you are ready to dish out the money for brushless (would cost double what you paid for your truck)
i wouldnt upgrade anything on the truck untill you break something.
ive never owned an evader so i dont know if there are any weak components to it maybe someone else could chime in about that.