I now have a solution that let me batch render boxes and a work flow that's pretty efficient. I've been going through and sorting out the various box sizes and will do new renders of all current boxes. There will be more different box sizes now (aspect ratios). It's a bit of work now to sort everything out, but after that it will be pretty easy.
Here's the old vs. the new version of the most common box. Not a big difference but OH so important!