As the title says, a checkbox that disallows the loading of mods with certain saves i.e. vanilla saves, to keep them separate from modded saves, so you don't have to manually disable all your mods to play a vanilla save and vice versa. This idea sort of spurred into life after I saw someone had a similar problem to me, except with a vanilla save. Maybe a mod profiling system similar to how Nexus Mod manager/Mod Organizer does it for Skyrim/Fallout as an alternative?