Your arrows show a good understanding of how forms flow through space and how to clarify form overlaps with shading. Be careful to avoid "loops" where your arrows end up close to where they started, as this can make them seem flatter. Also sometimes you are little conservative with your size increase as the arrow approaches the view. Just something to keep in mind.

On your organic forms, you do a job of keeping your forms simple. However, you are struggling a bit with keeping the variance in your ellipse degree consistent in the contour ellipses. While it is good that you are varying your ellipse degrees, these don't seem to be done in regards to how the form is actually moving through 3D space. Sometimes the degree of your ellipses seem arbitrary. Your contour curves do a better job of adding solidity to your forms.

Your textures are quite well done and it's clear that you took your time in these exercises. You obviously followed the rule of spending most of your time on observation and not relying on memory. My critique here is that in the dissection portion, sometimes when you are creating gradients of shadows, the lighter part of your texture can appear inconsistent with the darker part. All in all, well done though.

For your form intersections, you are drawing way too many forms on the page. Focus on drawing larger forms, take your time on each one, and how they relate to each other in 3D space. The sheer number of forms makes it difficult to assess your actual understanding of how each form relates to each other.

For your organic intersections, your number of forms is much more reasonable. However some of the forms are overly stretched or too complex. Keep them simple, like you did in the organic contours exercise. Also you are using a somewhat excessive number of contour lines. Only use lines that actually clarify the form. Too many contour lines result in visual noise and actually flatten the form.