Agree that these are looking better!
You might like to try drawing cubes to warm up and then filling in the sides with ellipses like in the example below (actually just found the site but it has a lot of good info if you keep looking, is it from another C77 poster?). I noticed after doing only pages of ellipses that it was harder to draw an ellipse in the context of the rest of a sketch, but this helps that.
