It's a great solution, I also think there is room for a NIP that includes the ability of a key owner to update media locations in the future, e.g. if you move from one server to another. To reduce the link length, it should be path-based and not rely on hashes. It would require a new event that contains path-mappings for an identity and I could have many, sending content to different servers.

Example image link:

"nostr:media:17e2889fba01021d048a13fd0ba108ad31c38326295460c21e69c43fa8fbe515/home/memes/onehourlater.gif"

"nostr:media:17e2889fba01021d048a13fd0ba108ad31c38326295460c21e69c43fa8fbe515/work/memes/onehourlater.gif"

If a link to video/image starts with "nostr:media", then retrieve kind X of the pubkey, which can have multiple different route-mappings that replaces the root (or other parts) of the path.

"home" could map to mypersonaldomain dot com, while "work" coupld map to myworkdomain dot com slash images.