Hello! Sorry crits are coming in a little bit slow. Here's my crit! In the future, do try to arrange the exercises in order; it helps with critiquing.

On your lines, I think they're doing okay. I appreciate the willingness to go for confidence above accuracy. Though, you do still have some arcing in your lines, especially in your planes. This hints at mixing pivots. I do like that you're messing around with the size of the planes, though. Keep on experimenting like that, I think its good!

Ellipse wise, I think that you've improved in terms of confidence from the beginning of the ellipses to the last exercise. This is commendable, great work! Still, some of the ellipses are mishapen. The general rule to prevent this would be to ghost a little more mindfully. With regard to the wobbling, do remember to ghost and execute with full confidence of your muscles. Try not to rely too much on your sight, this can lead to faltering in your lines.

For your boxes, a general note would be that you shouldn't try to correct your lines, even if they're incorrect. This would only serve to bring more attention to the mistake you made, worsening it. Overall, though, I think that these exercises are pretty well done. I will draw attention to your rough perspective, try to keep line quality in mind. There is quite a bit of slanted lines, and arcing lines here and there. And, in your organic perspective, try to introduce more overlapping boxes, such that you can use line weight to clarify said overlaps. Finally, the rotated boxes could be a little bit shorter. But, this one's pretty well done, so great job there!