I would make two plastic paper back-up and secure them in a bank safe (located in an other city or even an other country if you want really careful)
That's actually a really good idea. Although my bank accounts for my fiat money are all online banking. I think one of them has physical branches that I could use though.
Thanks, I don't like the idea of having a single paper back-up
If you are really serious and you don't want to think about it for a long time you can even have 2 paper wallets in 2 different bank safes in 2 different safe countries; you may want to use a simple code to secure the paper back-up but it can back fire, the code would be given to your wife, children, best friend and lawyer