No, see its all in emphasis, what makes rap rap.
What I do is record my main vocals with the exact way I'd do it if I were to perform live.
Then, double up on just the main parts I wanna emphasize (example: last part of each line), then i put them on a seperate track, lower the vol to the point where it is just noticable, and boom, got yourself a quality vocal track. Hope this help ease your worries about killing skills and whatnot.