I think you did a good job expressing the subject of size tiering very well! It's fun seeing the various panels. The characters are noticeable when zoomed out, though maybe for the upper right panel you could make the poses a bit more dramatic so it's clearer who is who.
I love the Dr's expression, she looks very grumpy, and while I like how friendly the two other larger characters were - their expressions were similar, and maybe this is a place you could have tried to vary how the others express happiness.
Great angle, I think you did some fine work here! Keep it up. If I had any suggestions, it would be to keep practicing your anatomy - doing photo studies will help, even if you later use this to inform your current art style.