Two should be enough in my opinion. One of storing and one for recovering in case something happens to the first device.
Don't use wallets like Jaxx and Exodus, they are not open source, you never know what's going behind the scenes and If they have access to your funds or not.
Store everything in one device, write the seed down in multiple pieces of papers and hide them in different locations. If the hardware wallet gets lose or damaged, you could use the seed to recover your coins.
Would/could you use several, for example Trezors, and program them all with the same seed, thus being able to access the totality of your bitcoin from any of the single trezors? Assuming your six number code, and pass phrase was the same with all the Trezors, which you can do with Trezor, if you lose one of the hardware wallets you would not even need to break a sweat.