Urist McScoopbeard, now that I have my own tablet and I'm drawing digitally I feel your pain, I wasn't zooming in when I was drawing and it really impacted what I was doing and I had no clue what was wrong until last night
That's what happens to my lines when I'm zoomed out. They're really shaky and I can't press hard enough to make them dark without making my pen wobble everywhere so they're thin and there's no weight. I'm definitely going to be experimenting with zooming to figure out what the best method is, I'm thinking I sketch zoomed out and do all my construction and let that be shaky, then I zoom in to do the main lines and be patient, instead of drawing the same line over and over using undo and not getting a good result in the end.
Fakeedit: As I type this I realize that I've seen that exact process before by other artists, such as Norasuko
https://www.youtube.com/watch?v=2vMOPH0Z7Rk