Practice pokes - feedback welcome :)

I've done a couple of sheets of practice doodles and am looking for feedback. Some of the lines are crooked and that was just 100% from me not being careful or going a bit too fast so I'll be working on that. I'm looking for feedback more about the quality of the lines themselves and anything else that stands out to less novice eyes.

Is it normal for my lines to be so doty? I know I can let a tatt heal and do touch ups, but how many times can you go over a line during a single session? Surely I can make them more smooth than this, could it be that the practice skins not taking the ink as well as real skin would?