Pen and paper is a old technique ,USB stick with Ubuntu is the safest.
Just because they're old, that does not mean that they're ineffective.
Hardware options are not included here ? Neither are other physical collectible coin wallets .
Don't use physical Bitcoin (art) for storing away money.
I voted for printed and cloud storage, i combine these two, but both of them are encrypted so even if someone would access there it should be decrypted first.
Cloud storage is a bad idea.
Hot wallet although it is encrypted, I rar it with strong password so no one can see transaction history and upload it to my second computer and to my email + cloud storage.
I wouldn't think that someone who wants to hack your wallet would be interested in your TX history, but that does make sense (I didn't think of this before).