That only works for complete (or "nearly" complete) binary trees, and you can't draw many of these since the number of children in a generation grows exponentia

That only works for complete (or "nearly" complete) binary trees, and you can't draw many of these since the number of children in a generation grows exponentially. For most trees you have to try to keep the width minimal while avoiding collisions between deeply-nested left and right children. One of the earlier papers to give some precise "niceness" criteria is "Tidier Drawings of Trees" (https://reingold.co/tidier-drawings.pdf https://reingold.co/tidier-drawings.pdf) by Reingold and Tilford, with a companion Pascal program for computing the coordinates.