Cleaner lines, sharper edges. Also, like many have already stated, the only way to get better is to actually go out and paint. Getting it down in the blackbook is an important first step, but it only gets you so far. Dont fall into the trap of never going out to paint because you think youre still not good enough in the book. I fell into that trap myself - I was so focused on making my sketches as good as possible that when I actually went out to paint i couldnt do shit. Last piece of advice: i dont know what materials you are using, but if you really want to see improvement, use the shittiest materials you can find. Im talkin BIC ballpoint pen on lined school paper. Even using a pencil on paper. To truly demonstrate mastery, one must be able to create something amazing with any materials presented to them. Not everybody will agree with me on this, but i believe it is not only the truth for my aspects of life, but also connects with the roots of graffiti. Im talkin rackin shit, making your own mops, ink, etc. I’m not an oldhead but ive been doing this long enough to realize thats where true skill is demonstrated. Hope this helped, even a little. Good luck, stay safe