All arts, all virtues, all upgrades, all characters in the inn and all EX levels? Anything else I'm missing?

I think you've got everything. I can't think of anything else.

How do we deal with Zone 7-2? I can't seem to find the artwork from there, nor the virtue.

https://steamcommunity.com/sharedfiles/filedetails/?id=3404398335

This guide has the locations

Thank you, I'll try to find them if possible.