I've thought a lot about this recently and even though I'm 99.99% sure I would never willingly enter another relationship ever again in this lifetime, perhaps in some other dimension where I'm single and not traumatized, I would consider a woman with the following traits.
Physically, she's feminine and I'm attracted to her, despite whatever level of conventional attractiveness she is. I have a particular weakness for femininity, and the girlier her gender expression is (e.g. make up, nails, dresses, the whole nine), the more I know I'm going to be in trouble.
In terms of personality, the very first thing I gravitate to is overt kindness, warmth, compassion, and even a bit of vulnerability. The last point brings out my natural instinct to be protective and defend (I know it's stupid and probably sexist/heteronormative but here we are). She will know without question I will offer full devotion, loyalty, and resources. Too much vulnerability means you're dealing with a bunny boiler, so not too much of this trait, but some. Also, has her own ambitions/goals/interests, is reasonably responsible (I don't want to be the only adult in the relationship), does not have active addictions (particularly to drugs/alcohol/cigarettes). In bed she tends more toward submissiveness only because it would be a more natural fit.