First thing I notice, is that your lines, tend to wobble quite a bit. They also tend to curve slighty.

To fix this problem I would recomend trying to do what uncomfortable mentioned. To try and purposefully curve your line to the opposite direction, that should even it out. Also that tends to happen when when you are not mostly using the shoulder pivot. If you are using the shoulder pivot correctly, then purposefully curving your line to the opposite direction should fix it.

Another thing Is wobbly lines, this will get better over time, but they do tend to wobble, Especially when plotting the lines for the perspective grid without a ruler. I would recomend ghosting your lines,beforehand.

You also have some fraying on the super imposed lines, Its ok, for now as you practicing your confidence of lines more than accuracy, but still something to keep in mind in later parts of the lessons.

Also for the elipses, the degrees need to change when doing the circles in the funnels.

For the ellipses inside the table you are also trying to make them fit into the table than making them overall smooth. Practice on getting them smooth than accuracy for now.

Another thing I notice, is that when you plot your boxes on the perspective grid, without the ruler. Your lines tend to not be perpendicular to the horizon line. This is very important and something to keep in mind.

With your organic perspective and rotated boxes, I notice that on some of your corners of your boxes they randomnly will have fraying lines. as mentioned before, Its important to practice your ghosting method during times like this.

Good luck and I look forward to seeing your progress, it takes time and hard work, but the ones who persevere are the victorious.