Your wpcentral profile would not crop so well. That's the main issue I have. I have numerous contacts that have terribly cropped profile photos now.
You are right. Cropping is an issue.
For one-head photo, circle makes sense. For multiple heads, because we took a rectangle-based photo and then re-fitting into a circle may not look nice.
I think apps should provide manual cropping so that the photo can appear better in a circle. But a better solution is to have an app specifically for taking circle-based photo so that all people's heads fit nicely into a circle. And people need to practice taking circle-based selfies
It's a matter of habits. Even square photos sometimes have cropping problems because the original photo was not in 1:1 ratio.