It would be good if you could get the total downloads of your addon from the details API. I'd like to display it on my personal website (next to a download link to WoWInterface) - edit: this doesn't matter as I just noticed it won't work because of CORS which is understandable, so it'll only work with postman, terminal, etc...
Also, minor suggestion but some of the changelogs are incredibly lengthy and I don't need to return this. It's a shame I can't ask for only the fields I need similar to graphQL but still using REST, maybe as some query string params. For example, the below could just get the filename, version, and title fields and ignore the description and changelog:
https://api.wowinterface.com/addons/details/<addon_id>.json?f=filename,version,title