I'll reiterate what I said. There's more blind faith in assuming that Hiura will upgrade the lineup given his demonstrated severe issues making contact in the majors over the course of his career and his stats since his rookie season.
Any "swing changes" and AAA stats serve to reinforce that "blind faith". Luke Voit, for instance, has a better AAA slash line this year than Hiura. Hiura's talented, for sure, but I'll have to see it at the major league level to believe that anything has materially changed for him at this point.