1. Who cooks for whom?
Juno cooks when she can. She was a mercenary so she's used to camping out and preparing her own food.
2. Who is the morning person/night person?
Varric is a total night owl and Juno is flexible when it comes to sleep, but she really enjoys the sun. The heat reminds her of the happier stories she's heard of Par Vollen.
3. Who is the romantic one?
Varric is the successfully romantic one, Juno is the awkwardly romantic one. She's very blunt and stiff so she'll try to be romantic and ending up embarrassing herself a la Aveline.
4. Who's the jealous one?
Juno, not that she'll really show it. Varric's a charmer by nature but her pride won't let her reveal her insecurities.
5. Who would lead in ballroom dancing?
Varric would have to lead. As the son of an (exiled) nobleman Varric would most likely know his way around a ballroom better than a Saarebas mercenary.
6. Who is the more cuddly one?
Juno by far. She loves carrying Varric around. He's getting used to it.
7. Who is more likely to pick the movie they watch?
Varric is a storyteller, Juno would trust his judgement in picking out the best stories.
8. Who is the one who pays for dates?
I imagine Varric would insist on paying for the lady.
9. Who initiates quickies during a mission?
Neither, the mission comes before personal feelings and they both know that.
10. Who would propose?
Varric would, but only after months and months of Juno dropping hints will all the subtly of a charging bronto.