If it were up to you what would the five rules for writers be for Diana? I mean this is one main issue writers don't have to do consistence. It's a little messy due to this.
I don't believe in rules for the characters. Bad writers will still write bad stories, good writers who don't get the character would still find ways to break things, and good writers who get the characters don't need them—the rules might even get in their way.
«Speaking generally, it is because of the desire of the tragic poets for the marvellous that so varied and inconsistent an account of Medea has been given out» (Diodorus Siculus, The Library of History [4.56.1])
I'm not against rules entirely; sometimes having some constraints or "bumpers" to work within help the creative process. Said another way to writers and artists, "here's the sandbox and now here's all the sand you have to create with."
I also think there's a lack of vision for Wonder Woman and her mythos that could be helped by having one or two writers and artists, who understand her, dive into developing her bench of allies and adversaries and concepts and weave them coherently into a tapestry that inspires other writers to want to work with the characters and concepts and take them forward.
Johns has done this a lot with individual characters (Black Adam, Sinestro, etc.) and whole teams of characters (JSA, Flash's Rogues, Green Lantern Corp, etc.) and it helped to explain why the character and their world is special and unique. Which not only inspired readers, but also other creators to play with the sand in that sandbox. Diana has tons of sand; what she needs is a sturdy, big sandbox built to contain it all.
Bad/inconsistent writing and poor vision for a character definitely hurts sales, but I think the times when comics were huge are gone in part because there is so much more entertainment and mass media out there in the world, so comics aren't so enticing anymore for many people. If general audiences want to see a superhero, they go to the movies or watch the TV shows. That's the future I think and merch.
Editors, writers and penciled are hurting the sales
People do not always waste money on awful things