I think it's funny in retrospect how Hans says,
"I've been searching my whole life to find my own place." and
"With you I've found my place, and it's nothin' like I've ever known before." during "Love is an Open Door", he's literally just talking about Arrendelle and not Anna at all. He even turns and points toward the kingdom as he sings that first line. So funny. It's actually more enjoyable to re-watch just to notice Hans' little underhanded mannerisms and words. Like when he calls Anna ordinary and then quickly takes it back so she's not offended.
And when Kristoff is singing "Reindeer Are Better Than People", he says
"People will beat you and curse you and cheat you." I know he's talking about the shop keeper when he says "cheat you", but could the other lines be hinting at his harsh life as a kid with parents? Maybe they were bad people, so he ran away as a little boy and found Sven and eventually the trolls. Or of course, he could just be talking about general past experiences he's had with other people in his life. Meh, maybe I'm reading waaaaay too much into it. I'm bored.