Mistborn is good because it doesn't' do anything wrong in my opinion. It has no big writing flaws that make me go "wow that was bad"
It tells an interesting story at a good pace with lovable characters and a unique magic system to tie everything together. On top of that, it has incredible payoff in the last few chapters.
IT's not perfect, because it lacks emotional weight in many scenes and tbh I didn't find myself "feeling" through the majority of the book. But it's powerful as a steppingstone for new authors to look at and understand what a good story should be.
I just prefer to be emotionally ripped to shreds when reading, but that in itself does not count as a bad thing, or something it could improve upon in any regard.
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