You do have that option of Settings --> User Settings (Admin Settings ? not sure - I don't have admin access) --> Notebook Settings --> Default indentation for Python cells (in spaces)

This will change the indentation for newer cells, but existing ones, I am not sure.

Maybe someone from databricks can confirm...

On the other hand if it does change, it will be pain considering it will show up as a change in git history and we will have to push everything again ? Not sure...