At least for us newer folks, it can be hard to draw the same clean line we get with the graver. Part of that is the difference in resistance between a graver plowing through metal and a pencil sliding across paper but another part is that we form the lines in very different ways since we turn the work into the graver.
Take your 'graphite graver', combine it with a clipboard with a bit of V channel glued on the back so you can stick it on your vise and now you can draw like you engrave.
Since I happen to have such a clipboard (idea from someone somewhere around here) I may just have to make one of those gravers and give it a try!