Just take the riser pipe inside and then you have the whole wall free in front of you. Depending on the shower, a narrow glass panel could be glued continuously there, for example. Likewise, there are all kinds of chrome shelves from Keuco, Giese, and many others. It also depends on whether you want the classic, i.e. one shampoo for "everything", or tubes here and bottles there... I would then choose the shelf accordingly, although the solution with the niche definitely works just as well, why not?