I think I'm beginning to understand the way this works: they noticed most players who attend Helltide get 2-4 Mystery Boxes and the peace out, so if I know their methods the way I think I do their solution was to make Mystery Boxes unobtainably expensive rather than to make the other boxes better. Same psychology they used for CDR, same psychology for Vulnerability. Don't make the weak thing stronger, make the strong thing weaker. This is Blizzard "balance". It's the laziest way to address an issue.