For anyone who is experiencing missing NPCs in their game, whether from uninstalling Open Cities Skyrim or for some other reason, here is a way to retrieve them. I couldn't find another video that covered this well, so I made one. Hope it helps you out.
Skyrim Missing NPCs Fix - Open Cities Skyrim Missing NPCs Tutorial
Skyrim: 5 More Unobtainable Items that you're Not Meant to Use - The Elder Scrolls 5: Skyrim Secrets