Let me make a correction, you only need to redo the Ellipses section. No need to redo the entire Plotted Perspective exercise.

Also, the reason why I'm asking you to draw through the ellipses is because your first pass is always terrible. As per Uncomfortable, your arm hasn't had the opportunity to fully understand the task it's been assigned on the first pass, resulting in a wonky and deformed ellipse. Its only in the second and third pass that your arm gets fully into the swing of things and can get to meet its full potential. Essentially, your first pass is maybe 60% of your actual capability, your second pass pushes it up to 85%, and the third one lets you get all the way to 97%. You could probably squeeze out maybe one or two more percent of ability by repeatedly going over the ellipse, but by that point you've made a mess. It's best to stop after two passes, because that both preserves the initial elliptical shape while allowing you to realize the majority of your potential.