I had think about this before writing a comment.
I like psych thriller movies, but not necessarily this one. Howard is certainly a conflicted psychopath with no redeeming qualities except being a good story teller.
Wallace is well on his way to losing his humanity but is stopped short. He, however, does not get off easily. At the end, he loses his GF, his best friend, and probably everyone else.
He does not have too much of his humanity left (a spoiler to say anything more). Far from running a show at the beginning; he is the exploited freak at the end.
A subtitle of the movie could have been, “Hannibal Lector meets Hemingway”. Hemingway lost. Depravity won.