Thanks for your perspective. I think I'll go with the safe side and wipe all old mods first. Two more questions:
Is there an easy way to wipe the data directory of old mods?
Do I also need to uninstall script extenders? Looking through the Vortex FAQs, it looks like script extenders can be installed manually without issue so it seems like those should be okay to leave alone? But as an inexperienced modder, if you think it's still safer to uninstall those as well and install them through Vortex, I'll do that.
I described that in my post..
Delete the Data directory manually delete it so you see it is gone, because if you use Steam to "Uninstall" the game, if there's mods/files in the Data directory, Steam will leave them there and not delete the directory, it will only uninstall all of the Steam files, and leave the game directory with all of the mod files still in it,
(This is the mistake most people make, they "Uninstall" the game to get rid of old mods, without knowing that the only thing that gets uninstalled is the Game, and the Old Mods get left, so then they install the game, and wonder why the old mods are still showing up.
1. Delete the Data directory, manually
2. Have Steam Verify your Files, Steam will download all of the files that Steam installed in the Data directory, and you should end up with a Data directory that is completely "Factory Fresh"
Yes, you'll have to uninstall/reinstall the Script Extenders because when you Delete the DATA Directory, the scripts from the Script Extender Zip Files, that go in the DATA\SCRIPTS directory will also get deleted, which will make your Script Extenders not work properly until you install/reinstall