Really miss this feature on the site. I didn't see a suggested features section in help. How might one suggest such a thing?
Use cases: So I can see non-official dependencies, 'commonly grouped together', chains of rebooted or reimagined mods, etc. Or mods that are related in scope or subject, beyond the typical categories. Heck, a TON of great mods I've had to really dig for, because they don't even appear under the appropriate category.
Otherwise. Maybe custom tagging, for more specific subjects?