Mistborn 2's issue is that Sanderson felt he needed to remind people about things. We get reintroduced to Allomancy (a poor fight, heck, Sanderson himself doesn't like the scene per annotations), we get reintroductions to characters.
I don't like reminders or reintroductions, i usually remember things, or check the previous work or from internet if necessary. (I do like having a list of characters or something like that though, negates the need for checking elsewhere.)
He has gotten better about this though, compare the Stormlight Archive to Mistborn.