Have a headcanon that I just made up on the spot for this post:
Tomo will be the first to be pregnant. Not married or anything, just pregnant. Most likely the result of some drunken tryst. The guy will marry her out of obligation and they'll have an awkward but ultimately okay relationship.
Osaka will be next. She'll just settle down and have her kids and her husband. And most likely spend the rest of her life keeping them all on their toes with her weirdness.
Yomi will graduate, and come roaring into the workplace at full tilt. She'll then burn herself out by working crazy hard while simultaneously tiring of the horrid way women are treated in corporate Japan. She'll bail, meet a cool, Scruffy-esque sort of guy who doesn't make his living as a salary drone, and happily settle down with him.
Sakaki isn't going to make it as a veterinarian. It involves killing too many animals. She'll realize this, get out, and become a gifted florist. Eventually she'll meet a tall, friendly man who brings her out of her shell and likes cats, and marry him. She'll have more kids than any of the other Azu-girls. And still somehow be smoking hot as a 40+ year-old woman with 4-5 kids.