Snape? He wasn't evil or selfish (although he seemed that way, but he also knew what was up. And, let's face it, Harry's father was a jerk.)
Maybe not evil anymore, but he was still pretty selfish, imo. Yeah, Harry's father was a jerk, but Harry isn't his father, and devoting a full six years to making Harry's life miserable (even if he
was actively trying to save that life), for no better reason than that James was no longer available, seemed like some rather petty and selfish behavior to me. As did bullying the Gryffindors because his archnemeses who are no longer in school were all Gryffindors. There's really no excuse - not of the Freudian variety (the man is supposed to be a professional, and if he can't behave professionally then he shouldn't be teaching), and not his role as a double agent either (he could've just told Voldemort that any show of hostility toward the Gryffindor students would have made
Dumbledore suspicious of him). Did he act heroically? Yes, Merlin yes. But his day-to-day treatment of the students is a separate issue that can't just be swept under the rug because of it.
Mikkel, I would say Hufflepuff. I was actually torn between Hufflepuff or Ravenclaw for him, but he just seems kind, loyal, and humble enough to be a Hufflepuff. In general the fact that he's taken up the position of Team Dad seems pretty Hufflepuff.
Actually, am I the only one here who thinks that Mikkel would make a really good Slytherin? He's occasionally sneaky, enjoys trolling people, isn't above bending the rules to get what he wants, and even attempted to manipulate Sigrun ("Really, there's no need to get mad, all I was doing was saving you some work"). I could totally see him as a less extroverted and more quiet Slughorn, seemingly inconsequential but quietly pulling the strings behind the scenes...