Idea to encrypt wallet with gpg and spread it over world is awesome. But in short term it seems overcomplicated to work with it at daily basis(is it not?) and in long term you are still depending on private key (another storing or loosing problem...)
It's an encrypted backup, not an active wallet. Day-to-day use is with your secure client, and you update your wallet backup occasionally, although probably less often than you think.
Paper wallets tend to be unencrypted. If someone breaks into the bank, and steals the QR code with your cold wallet private key, you're screwed. If you've got a backup of an old cold wallet that's encrypted, but you don't remember the password(s), you're screwed. If you have a single backup of your cold wallet as a paper wallet, and both the backup and the offline computer is destroyed in a house fire, you're screwed.
GPG encryption is going to be more reliable than virtually any physical security you can name, assuming you select a secure enough passphrase. And a digital file who's security you trust more than any bank vault can be copied anywhere, making it virtually impossible to lose all copies.
grnbrg.