Having watched Frozen, I can say: Not amazing like Tangled, but nowhere near as bad as its detractors say, either. I liked the characters quite a lot even if I shook my head at quite a bit of the movie itself.
Having said that, this "How It Should Have Ended" was pretty entertaining.
It's not a patch on the Pacific Rim one, or the Star Wars ones (at least one of which seems to have been blocked) either, but everything before the music number at the academy was basically perfect.
(...I'm not a fan of musicals, which is ironic in context, I know.)
*Actual things I've thought about saying in relation to this movie completely unironically before recognizing the puns:
Ice powers are the coolest elemental powers.
That scene where their voices are clashing as they sing gives me chills.
I kid you not, those were both conjured entirely accidentally by my brain.