From Proposal to Example: CSL Gallery
So rather than just a CSL creation wizard, I realized it might be more sensible to do a full-blown web app. Am not the best coder, but am making some progress. Here’s the list of categories:

Here’s the (start of the) detail view of the APA style:

I’m using Django, which is nice. I got this together—complete with a full admin interface and multi-user authentication backend that comes for free with Django—in a few days. There’s still a lot of work to do (previewing, feeds, actual CSL generation, etc.), but I think this is promising.
So the idea is really an extension of the Zotero CSL repository, where accessing a style by its URI in a browser will give you the HTML view, complete with preview, but requesting it with an alternative CSL mediatype will instead get you the actual XML style file.
Of course, the real hard part will be in making it really easy for end-users to create new styles. But, I think I have the solution for this: most of the styling work will get handled with pre-assembled macros. In essence, I’ve built the class/table model based on what I outlined in the earlier proposal.
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