In my experience, Convert Lines To Fills can often make a huge difference in how a piece "reads," especially when displayed at smaller sizes than you originally drew it at.
I get the impression you're struggling to place lines and points exactly where you want them. By any chance, are you having trouble with curved lines changing shape when you drag them? If so, the fix is to temporarily add a line that touches the curve at a point you want to anchor. Anchor two points on a curve in this way, and you can sculpt the line between those two points any way you want without risk of those points changing.
I know you asked for style and expressions feedback, not surface, but in this particular piece I honestly feel like the surface is throwing the style and expressions "off" from what you probably intended.
Good luck!