Here is my admittedly somewhat vicarious list:

Properly calibrated BS detectors
Sense of humour (and irony)
Acceptance that we live in an imperfect world
Possessing the skills required (and luck) to achieve a realistic level of self determination
Ability to self-regulate
Ability to find contentment from multiple sources
Having empathy and compassion (but knowing when not to make a casualty of oneself)

And when the time comes, having the luck to find a realistically compatible mate

Become what you are