Hi o/
Unfortunately I don't think the link is working, when I opened it, the link led the imgur's main page and displayed "The requested page could not be found".
Looking forward to seeing the exercises!
What you did followed a clear idea, and you worked diligently enough to not distract from the idea. You traced the shape of the model with clean simple lines, adding contour lines to indicate volume. You abstracted a lot of details, like the specific clothes, the minute curvatures produced by fat tissues and muscles, and the lighting in the reference, to produce an abstract grid. Even if you wouldn't have underlayed it with the photograph, the grid you developed would give a very exact impression of one way a human body can relax, while laying back in a lazy or contemplative mood on a chair.
This is certainly a very valid way to simplify the reference you worked from.
I can't tell you whether you "nailed" it, as I am not entirely certain, whether you have a specific goal in mind going forward, but doing this exercise must have deepened your understanding about the human body. I have my own specific taste in how to develop a figure, and I watched and read enough explanations from other artists about their methods, so I could try to compare your approach to the reference to the way someone else might do it. I am just not certain, whether that would help or hinder you on your path.
TL;DR I find your result beautiful.
These look great. In poses where the head leans forward or backward, you might consider a curved eyebrow line, to wrap around the head, but that's just my personal preference. And I don't see anything else that you might consider doing differently. You nailed it!
Wow! These look great! I love how you broke down the shapes of the leg and how you broke the thigh and calf in half to show that break in form! I agree with Katt Quiet in regards to curving the eyebrow line (I'll be taking that advice for myself too lol) Other than that, your process on deconstructing and simplifying the shapes look great! Keep it up!