Stole this one from someone else but: love love love classification AUs where regressors and caregivers suffer physically when they don't meet their needs. **especially** when we get to see the caregiver be the one not fulfilling their needs!! like yes give me caregiver who doesn't have a little but doesn't think it's important/doesn't care only to find themself suffering the consequences---maybe it's irritability, depression, a weakened immune system, or something more specific like long-lasting tension headaches. Maybe they stumble upon a little who can't find their caregiver at the grocery store or something and so they have to take care of them for a bit while they search for the cg---and then realizing, huh, that headache I've had for like, a month, suddenly disappeared?
or caregiver accidentally taking care of/babying their friends subconsciously...watching TV on the couch with their roommate and unknowingly drawing closer and closer until they're borderline cradling roommate and the roommate is just like. kind of awkwardly accepting it and mentally making plans to sign the caregiver up for some sort of babysitting/volunteer daycare program, because as nice as cuddling is, it's kind of annoying to be fussed over all the time.
okay i've talked a lot about the caregiver side of things but some regressor stuff i love seeing/would love to see more of: ugly symptoms of headspace suppression. Like deep depressive episodes. Or lashing out. Gosh I would love to see more lashing out---give me a regressor who gets cruel, violent, even, when they've gone too long without regression. Bonus points if the society they live in has all sorts of laws and regulations to ensure regressors properly meet their headspace requirements---but only because they know of the destruction Littles cause when they don't regress frequently enough, and being a Little is super stigmatized because of it.