That he is not flaky
This is an extension of keeping his word, but it’s so much more than that. You can get caught in a cycle with a guy who consistently cancels your dates at the last minute for “very good reasons.” And maybe the reasons are good. Maybe he has a very demanding job where emergencies come up often. You aren’t necessarily passing judgment over his commitment to his job. But you are allowed to set this standard for yourself: I want a partner who can make me a priority and who has space in his life right now to prioritize a romantic relationship. An on-call doctor who has to bail often to tend to his patients isn’t a bad guy, but it’s okay to admit to yourself that he may not be the right guy for you if you don’t want to spend a lot of time (some major holidays included) alone.