I don't see him outselling Luther in any way. Luther has more interesting parts and works better for customs, as well as being more famous himself. I don't think I've read any of Mann's works, but I just looked over the summary of Death in Venice and
. It's just as well they didn't make a klicky set of the main character stalking a child.
I suppose it also depends on the writer in question - for example, with Dickens you could probably make some recognisable characters in Klicky form, but what would be the difference between a figure of Jane Austen and a figure of one of her heroines?
Austen characters would make more sense as duo packs or larger figure sets because the novels are more about the interactions between the characters, rather than one character being the main focus. And Austen spent more time describing houses than the physical characteristics of her characters, so we don't have identifying features to portray.
Austen herself would need either her writing table or her iconic writing box. If they wanted to go above and beyond, the patchwork coverlet she worked on with her mother and sister and brewing equipment - she brewed a good deal of beer and mead.
Dickens doesn't need as many props because we have solid portraits of him and that beard is something on its own.