So what toolbag or workshop of excellent specialized tools would provide the same capability as GnuPG?
I'm somewhat amused that every time this kind of discussion comes up, the answer is "you are holding it wrong". I have a feeling the world of knowledgeable crypto folks is somewhat detached from user reality.
If a single tool isn't possible, give me three tools. But if those three tools each require separate sets of keys with their own key management systems, I'm not sure if the user's problem is being addressed.
> I want to be able to encrypt my backups to multiple recipients.
Presumably this means you want to encrypt the backup once and have multiple decryption keys or something?
The rest of your original comment are constraints around how you want it to work.