Hey @Robert_Imhoff,
as of now it’s only possible to add artist images manually. About 2 years ago this information was posted in another thread.
An image must be at least 960px wide and have a aspect ratio greater than 1.55 to be given the full banner image treatment.
The pretty much sums it up. There is quite some room for improvement and your input would be a nice option of making the workflow smoother.