Yes you are worrying waaaaay too much. But I think if you wanted to work on one thing it would be making your vertical lines as straight (vertical) as possible. That’s where the drafting aids come in. But I have discovered some really nice pens. I have been using Pilot Fineliners for years but the nibs don’t last very long and then they are worthless. These pens are made by Copic and called multiliners. They have repllaceable ink cartridges and nibs. Pricey, but you don’t need many. Also have a variety of nib sizes. See attachment. -Miles