I only take exception with the "Frozen didn't fix Maelstrom's brevity" critique.
While it isn't THAT much longer, it does have added show space that Maelstrom did not have.
Frozen is roughly 1 extra minute from start to finish based on reviewing a few videos ... or a 5 minute ride vs a 4 minute ride.
Now critique of the art direction / set design / AA's is another thing, but I don't personally think Frozen is a short attraction, the ride time is decent for an attraction of this scale.
But it perhaps can still feel brief, which may be a result of Disney shoehorning the ride into a layout/ride type that doesn't particularly work for the story.
But it's a more complete experience than Maelstrom was.