OK, here is your response, Talo.
What you suggest makes sense. Nifty Archives has such a system, but the author needs to submit it into a category in advance. Then their huge site is divided into sub parts which is fine for those who have limited interests...
AwesomeDude, however, has always been - if you like - a boutique site where the quality of a story is the important thing. It is not organized as a department store where various and sundry items are sold according to a wide range of categories. We are primarily a gay fiction site but many of our authors also post stories on non-gay related subjects.
I've received a lot of correspondence from readers who come to AD because they are likely to find well-written stories by their favorite authors about almost anything. That's what they expect.
I've recently added the Coming Attractions Forum so that authors - should they wish - may give an idea of what to expect in a new story. It is not compulsory, nor should it be.
And some authors think that putting their stories into boxes limits them. And if one thinks that Michael Arram - a published professor of Medieval History at a renowned British university writes 'fantasy' because an 'elf' appears in his current story introduction, then one probably lacks the imagination to really appreciate good fiction in the first place.
We are a free site - maintained by donations. We don't have the resources to develop and maintain a data base system to categorize stories or implement such across the thousands of stories already on our site. We are basically a minimally managed site with volunteer labor. Our authors arrange for the editing of their stories. We pay attention to the quality of the stories we post and their visual presentation, something most other sites ignore.
Our best resource is the corps of authors who meet here and discuss what's good for the site and what's "doable." I am always willing to discuss ideas here to improve our service to both authors and readers.
Mike