Great work ! For the cylinder, the more you go away from the horizon the more you should see the ellipse. Here you have 1 circle too wide that is clearly a mistake. You could also widen a bit the bottom ones. For form indication' there is no clear rule. I find yours really good. I have done way more myself without a clear result. Keep going !
Paintovers (1)
Beginners roadmap Section 3 workout
Artist's notes:
I am unsure with the perspective of the rounded elements. And how to improve indicating form with contour, how not to over do it? Difference with shading?