Hannah. Hannah's best attributes are Wisdom and Charisma, and I have often said that I will not be surprised if she winds up going to semminary. So my first cut was to say that she should be a Cleric, preferably one who wears light armor and focuses on ranged spell attacks. But then I remembered her nascent singing career, so I settled on Bard (College of Lore). She asked what race. I said Half-Elf or Halfling, because my older daughter is short. She liked all of that.
Emma is our family genius. Her best thing is very obviously Intelligence, followed by Charisma. That made the choice easy -- Wizard (Illusionist). What race? I said Human.
Sally is my wife. I don't know that Dexterity is really her best thing, but I suppose it could be, and her Wisdom is certainly very good. Plus, she's definitely trained in Perception, she lived in wilds of Paraguay for almost four years, and she is by far and away our dog's favorite person. So... a Ranger (Beast Master) named Salmuta, a half-elf and the youngest of six but the only sibling with any elf blood (oops!). We sat drinking some beer and creating a whole back story for Salmuta after we got home this evening.
That leaves me. Like Emma, my best thing is Intelligence, followed by Constituition and then either Strength or Charisma. My Dexterity is below average. I was a soldier, and now I'm an engineer, and you can model my history pretty easily using the Fourth Edition ruleset. Either I'm a Warlord/Artificer or else I'm an Artificer with the Soldier background and whatever feat gives you Commander's Strike. I'd say Human for my race.
The only problem with all of this is that it doesn't give our family's party a front-ranker, at least according to the 5e ruleset. I don't think of myself as a brawny guy, but there aren't many front-rank melee choices for characters who aren't Strength-based. I hate to admit it, but it's driving me crazy.