Hello, I tutor architecture computer software but I do art too so here is my answer. Unless having outlines in the final artwork is your goal, I would not recommend inking over your initial pencil outline. Usually artists draw their initial outlines very lightly, using a not-too-soft lead, and very judiciously, then they just color over it. Some even skip the pencil altogether and draw the initial outline with a mid-tone colored pencil, so when they color over it the lines become a part of the drawing. There are other techniques to help you keep the drawing clean too, such as using an underhand pad to avoid skin contact, using eraser bean bags, or working from the center out.