Hello there, Iβm a little late tk the sketchbook but welcome! Nice to see al the practice, those cylinders and cubes and measured copies are super useful
I think youβre doing great, if there is one that that stands out to me at this point it would be the lines themselves. I would recommend to experiment a little but in the end you want longer, more flowy lines. To achieve that you just practice doing all the other stuff but try to make fewer lines and only draw what you mean- else you kind of caress the canvas and get fuzzy lines. Drawing from the shoulder and using alll the canvas helps
The other thing would be to do plenty of gestures, it definitely helps your linework be more expressive
Cheers and keep it up!