I think you're heading in the right direction here! Your CSI choices are solid. There's no quick fix for line quality, in my experience it's something that develops similarly to exercising a muscle, a skill you build. Getting in the habit of drawing with long, tapered strokes will be tough at first but as you build the muscle memory you will improve. Just keep practicing and staying conscious of it.

I think your edges look great! I can clearly tell when one value ends and another begins -- and great job not outlining your value shapes. I would say that your value range could be expanded a bit and that will help you add more contrast in the lighter value range. I made this visual aid to illustrate my point. Hope this helps!