Any authentic sutta from any tradition that gives guidance on what kind of partner to choose? Any authentic sutta or part of sutta from any tradition that gives guidance on what kind of sexual relationship partner to choose?

I'm thinking the Vimalikirti sutra should say something about such layman concerns.

Specifically things like what kind of partner would an ideal layman choose for family purposes if choose at all?

Should one find a companion who already understands the Dharma and is thus highly capable of being a companion and teacher to children?

Or is the proper bodhisattva action to practice the dana paramita by bonding and inspiring  someone who lacks the dharma--but is ready to receive it--and thus help to transform their karma as well as the whole universe's (through increasing Dharma quotient in a "lower denominator")?

[The Taoist tradition (which I highly honor) has some insights into this matter and for me is very connected to Buddhism and according to my learning would imply that a cultivated woman choose the latter and a cultivated man choose the former.]
Here's a summary of Chapter 5 of The Buddha's Teachings to Laypeople: Practical Advice for Prosperity and Lasting Happiness.


If you fail to find suitable associates it's better to be "like a solitary rhinoceros"
Leave aside unproven traditional criteria: including race, caste, gender, and external appearance (and creed)
A person's inner development is more important than their birth
Be cautious of first impressions and initial understandings


  People cannot be know well by their appearance
  Nor can they be trusted after brief impression.
  Yes, the undisciplined may roam in the world
  In the attire of the well displined.

Associate with a person, observe and evaluate their words and actions
Be wise and rational in order to obtain a clear picture of the person you're evaluating
Find wise people who cause no fear or worry
Look for someone who is compatible in four ways:


Similar confidence in spiritual development
Similar respect for self-discipline
Similar respect for humanistic practices
Similar level of wisdom


These similarities are "so important for a peaceful marriage".


Spiritual development: if one person respects spiritual believes and practices, and the other holds them in total disregard, then the two people are simply incompatible.

Self-discipline: if one partner is well-disciplined and the other unscrupulous then their incompatibility will become obvious and cause problems.

Humanistic practices: includes dana, also caga (generous acts).

Level of wisdom: i.e. samapanna, includes knowledge, skill, emotional maturity, reasoning power; doesn't mean that both should have same education and intellectual ability, but wide difference in these areas could cause incompatibility and lead to conflicts.

Chapter 6 is about how to treat your partner after you marry.