Hi, I record sounds like this for my job. There's a lot of things to discuss of course, but the first thing is why do you need that sound to be so loud? It's a quiet sound and really does it need to be crazy loud? But anyway, there are some ways to get more loudness, try writing on something resonant, for example of cardboard box. Also think about the psychology of sound, for example if you see a video of a pencil writing, the sound might actually be something else entirely, like a piece of wood on some construction paper. Another way to make these types of sounds sound huge is with contact microphones. They have their own issues but for friction noises like pencils they can be pretty magic. If you're not in a studio your mic is picking up all the background too and besides noise reduction is usually part of the process anyway, and if you are mixing the sound with other things you can be fairly aggressive if you are careful.
Edit to add: A lot of the time a shotgun mic isn't the best choice for quiet sounds because the interference tube is so long that the actual mic element is further away than you can get with a cardioid for example.