How is my tree?
It is easy in this Instagram world we live in to get caught up in what the pose looks like instead of the benefits of the pose. The intent of tree pose is open the hips. While the single image is a little bit exaggerated, I have seen it.
The double image is ideal. Why, because the student has opened her hip. That's where the focus is - not on how far up your leg the foot goes (often putting pressure on the knee) or reaching arms over head (while sacrificing alignment). The best part is either student in the third image can be you in today's practice. You decide.