In plotted perspective, one box is not filled with hatching and hatching of another one extends to vanishing point, be mindfull of those details next time.

Lines

Lines are good, but you fray lines sometimes and arch lines. A little wobble here and there, but not always, be confident when you draw lines, even if they miss.

Remember to place the tip of the pen at starting point, exactly where you want to put it. The lines don't start at starting points mostly in box exercises, probably due to distraction that is drawing boxes, remember to focus on lines when you draw.

Your lines suffer from arching a little bit, probably due to the fact that you do not use your shoulder pivot, but elbow pivot. Try to use your shoulder more, and what helps a lot for me is having my drawing surface at an angle so I can engage shoulder more (nothing complex, just a board supported by some books).

ellipses

Ellipses look great, one detail is that you sometimes do a lot of rounds around the ellipse. Two loops are totally enough, and I think more than that results just in scribbly mess. Other than that, good job.

boxes

As I said, your lines are worst when you draw boxes, remember to make dots inbetween the lines and then use ghosting method to draw a straight line, don't freehand the line while guessing at what angle to place it relative to the box. You will get more "box intuition" in 250 box challange so focus on making straight lines while drawing boxes, and thinking in perspective.

In rotated boxes exercise, the "box ball" is half the size. That's a mistake because when you make bigger boxes, it shows where you make mistakes so you can learn from them. Other than that it looks good.

You are ready for 250 box challange, just be confident in your lines and use ghosting method.