My Essentials For a (Hopefully) Lasting Relationship
First and foremost, mutual openness, honesty and truth. These are essential from both parties. From these will come trust, the underlining foundation and basis for any relationship.
Second, a true friendship based on the above. If you are not good and dear friends, who enjoy each others companionship and company, why would you want a commitment to a life spent together?
Third, a matching moral and ethical standard of values. If not matching there will be conflict, in my opinion. In my case this requires her to be libertarian in spirit and action. Consideration should also be given to compatible diets and approaches to medicine, doctors, etc.
Fourth, a compatible spiritual belief. They certainly do not have to be the same but they do need to be compatible and not in conflict.
Fifth, a compatible and shared life goal. If one wants to travel and the other wants to be a homebody it is difficult. Not impossible but difficult and certainly not what I want.
Sixth, a compatible life style. If one wants to live in the country off grid and the other in a metropolitan high-rise or even if both want to live in the country but one wants a nice house on a hill with a barn and horses but the other wants a small cabin in the woods with a few chickens or goats, it will cause a conflict or disappointment to one or both.
Seventh, Who’s in charge? Of the house, money, the garden or of security. Often these determinations are a natural and mutually agreeable aspect of two people but when there is a conflict, it can be shattering and divisive. Arguing can be a destructive influence on any relationship, especially when living together in close quarters and these aspects should be worked out before a commitment.
Eighth, a mutual pheromone attraction. This is not absolutely critical but sure helps in getting along

Unfortunately, this last aspect is usually the one that first attracts two people to each other but I do not believe that it alone will hold a couple together over a long haul. I am convinced that this should be postponed until after the first seven have been determined to be mutual. Then jump over the broomstick, best wishes and good luck.
These are just my criteria, not ones I am suggesting for others, although I believe they should be thought about and discussed. Maybe that’s why I’m still single, 20 some years after I divorced my first (and only) wife. But these were all aspects of contention in my marriage, some more than others, that were harmful, hurtful and hell.
If you can add some other aspects that you have found helpful or that you feel would be beneficial, please do.
added MamaLiberties suggestion below.