I just don't see Rolf and Shir together. Shir is a rich girl who goes and steals stuff because she has nothing better to do. She's kind of like the Paris Hilton or Lindsey Lohan of Motavia, and you don't see them dating professional guys with respectable jobs like Rolf. I could see her with more of a bad boy like Kain.
If I had to pair them off, I would put Amy with Hugh, since they are both doctors. But I could also see Hugh as the Platonic friend, who harbors a crush for her.
So If I had choose it would be Amy, but I really don't like Rolf with anyone other than possibly Nei.