1) Values - Part one of the holy trinity of predictors of relationship success. Loyalty, family, friends, respect, manners. Any woman with shallow priorities like constant Facebook posts, instagram pictures, hittin' the clubs should be immediately discounted as LTR potential. Not saying don't go have fun with those girls but if you want a woman for an LTR she should be the kind of woman who shows up on time, says please and thank you, respects everyone around her and puts her friends and family before herself.
2) Mental Health - Part two of the trinity of relationship success. Most people have some struggles with depression and anxiety, but if you notice anything above average about a woman's mental health, like self harm, horrible depression, drinking excessively, drugs, then chances are she'll be an unstable partner.
3) Communication - Part three of the trinity. It's very unlikely you will find a woman who is on par with you emotionally. Despite how politically incorrect it is, estrogen makes women more emotional. If you want proof, go google about people going through HRT (hormone replacement therapy). They experience the extremes of male and female hormones. So what you want is not necessarily a woman who has perfect emotional stability but one who can move beyond that and discuss things calmly. She should be able to communicate her feelings clearly, she should be able to ask for things she wants and tell you when she doesn't want something. This is massive in the bedroom too.
4) Personality - Has actual hobbies, actual goals, is friendly and has a good sense of humor. She should be able to take a little bit of ribbing like the boys and give it back to you as well. Having similar hobbies isn't really as important as being able to have some fun while just sitting in a silent room. I won't go on to much about this as some of it is personal taste. But if you settle with a boring woman because she's hot, you will eventually get bored and so will she.
5) Impulse Control - No excessive drinking, drugs, shopping, gambling, sex, risky behavior, emotional instability etc etc etc. Basically anything which looks like a woman is abandoning her better judgement to "have fun" or "be free" is a personality trait that is absolutely guaranteed to bite you in the ass. Very high risk for infidelity or monkey branching, dragging you into drama, swallowing you in debt, getting bored with you. These behaviors are symptomatic of number two but it's an important trait in its own right.
You guys have seen me do similar lists with more traits but honestly these five are the big ones. Find a woman who is moderate to strong in all of these and she's highly likely to make a decent partner. If she is weak in any one of these you should proceed with extreme caution. Of course people lie and people change so nothing is a guarantee.