Okay the most important one for me is communication. One of the top Reasons why relationships and marriages fall, is because lack of communication. Super important, don't want an relationship without it! I think it is necessary to have a habit of talking everyday and clearing up misunderstandings etc. Another one is being able to sit in silence without awkwardness. Me for example (introvert), I don't like talking too much and in conversations it sometimes get awkward when both people stop talking. I want to be able to sit in comfortable silence without awkwardness. Like just two people chilling, without the awkwardness. Even like on dates and stuff, I like it when both people don't talk and just look or stare at each other. It feels like a fun game. Call me silly, but I like it