I disagree that PEs should be disqualified if they show very basic "care" for close relatives or friends, even Hitler "loved" his dog.. the fact is an absolutely evil monstrosity of a character can still have basic comfort from a select few.. otherwise they are just one-dimensional, drooling idiots.. psychopaths of the highest degree can have people they "care" for (or at least won't torture as much as others).
this is my main beef with PE / CM as a trope, completely unrealistic.. even Alan Yates had some level of concern / affection for his girlfriend.. the fact is he still abandoned her in the end.
I think PE can show a degree of concern / affection for select individuals as long as it doesn't detract from the fact they are still horrible entities.. sure you may love your daughter or spouse or that guy at the bar you get drinks for and find a "friend" but it sure as hell doesn't make you any less of a monster if you also have a basement full of starving orphans you like to saw in half after your done.. if you are caring to some but horrendous to everyone else I'd argue it shows you as a far more disturbing and fearful entity than a "always chaotic evil" / "don't care for anyone ever" stereotype.
a being incapable of love / affection is scary.. a being who can show some degree of affection to others while also being able to inflict unspeakable horrors on others is TERRIFYING.
just my opinions.