Currently the "Delete existing cover art" option with the context of import a single cover, sounds to me like it would only do it for the selected import type (e.g. front cover) but it deletes all of them. This makes action not useful at all for me since I would have to export and add everything back anyway.
I would like to see a replace cover of same type option, where it would leave the other art alone and act like I am using the right click replace cover option.