It is what I mean, but I am fascinated that I find that ballpoint works better for me for those purposes. To be fair the ballpoint I use took me a while to fin

It is what I mean, but I am fascinated that I find that ballpoint works better for me for those purposes. To be fair the ballpoint I use took me a while to find - Parker Jotter case with refills they now call "QuinkFlow." They write smoothly without requiring much pressure, with quite a thin line. The only pen I found that can produce a thinner line is a Pentel Needle Tip with a 0.3mm ball. The thing I love about any ballpoints though is that they are pressure-sensitive - they produce a lighter line with less pressure, which is great for sketches and shading. I find that rollers are either on or off. I never experienced the ballpoint ink not drying, in fact the opposite - ballpoint is usually dry instantly, while with rollers I have to be mindful and wait a few seconds or more with pooled ink. The only issue I found ballpoint has that roller doesn't is the "ink turds" you mention. These happen especially when I try to draw long straight lines (maybe even with a ruler). At the end of the line if I'm not careful I can end up with a giant drop of ink that can turn into an unsightly smudge. But, I found a way around it - I need to keep rotating the pen so that different sides of the ball enclosure collect the ink, letting the collected ink get pulled into the paper.