Firstly, for the rough perspective boxes, it helps considerably to go over your completed work as described here to help identify where your estimation of perspective tends to drift.
Looks like my estimation drifts off everywhere, mostly. But a big issue is that parallel lines aren't converging fast enough, i.e. the vanishing points are very often too far apart.
Lesson one: https://imgur.com/a/glPBj
Day 3 was just a mess
5hundredand5 in the post "Lesson 1: Lines, Ellipses and Boxes"
2018-01-27 09:07
Looks like my estimation drifts off everywhere, mostly. But a big issue is that parallel lines aren't converging fast enough, i.e. the vanishing points are very often too far apart.