1. Elsa should be really messed up after years of solitary confinement
The beginning of Frozen is deceptive in its cuteness; you're so busy humming along to "Do You Wanna Build a Snowman?" that it's easy to forget the depressing and twisted plot setup. For whatever reason, seems completely normal to us that -- after Elsa accidentally hurts her sister with her mutant ice powers -- their parents take the advice of the local rock trolls and lock Elsa away from the outside world. As it turns out, keeping a child in a single room for her whole life has negative consequences! By the time that catchy number ends, Elsa is a powder keg of fear and neuroses.
The big emotional arc of the movie involves Elsa conquering and controlling her fear, but nobody gets the blame for irrepairably damaging the psyche of a little girl. The parents have the convienent excuse of being dead (or at the very least marooned on a tropical island), and the supposedly sage trolls see no problem with recommending what amounts to the prolonged torture of a minor.
We never really see Elsa leave that room before the coronation -- we're under the impression that she stayed in there for at least like a decade, with hardly any human contact. It's like something out of a prison movie, with fancier furniture. When mom and dad go to Disney Heaven with Mufasa and that baby gorrilla who gets eaten by a leopard in Tarzan, Elsa is so used to the fear that her parents instilled in her that she stays inside even though no one is alive to tell her to. She continues to let Stockholm Syndrome run her life, even though she doesn't have any captors. No wonder she snaps immediately when exposed to civilization.
This is nothing to speak of her health, which is probably pretty awful after spending her childhood in an 8x10 box. Not only is it tough to get any real exercise, Elsa hardly gets any sunlight apart from a piddly window. At the most vital time in her life, Elsa was deprived of the most basic ingredients she needed to grow, emotionally and physically. By the time the plot starts, her bones should be incredibly brittle and fragile. Hell, this hug at the end should break her in half.
"But this is just a cartoon!" you say as fast as you can, sort of spitting at me a little bit. But I'd say a movie that pokes fun at the "Get Married to Someone You Just Met" trope is willing to take a few jabs. Especially when it ignores just how much Disney movies like to lock up their women.*