Excessive kindness to Xiao Yan and Yao Lao, yes Yao Lao did teach him alchemy but that was after exchange of treasure not that Yao Lao does it out of kindness so therefore there are no kindness that needed to be repay. With Xiao Yan it is the same but MC like helping both of them so much, which establish that MC like to help out people but then decide to kill the glutton of flame that he practically raise and act like cold blooded animal (Ch 576).

Story has a lots of details but can't really tell which one to focus on, also MC personality is problematic, can't really tell if the MC should just be a evil & neutral person, or is he just a person with little compassion and some evil to achieve a goal. MC got no reason personally for a lots of the things that he does and it just seem very vain and is just because.

Good MC lose brain against villain and suffer.