Such great information!! When I first started out I was doing exactly what you shouldn’t do. I had a ledger book with all my passwords and keys in it. I started keeping in the notes section on email and phones but I’m really liking your idea with the spreadsheet on a USB. The two factor authentication is something I’ve done from the start. I’m really not sure why people are given the option. It only makes sense to do this. As for coin storage I was never sure what to do at first but wanted safety. Research showed me how to create my own cold storage on USB drives but with the introduction of storage hardware it makes things much more convenient. The only issue is the various altcoins that these devices might not support.
A sevice that is coming that has me extremely excited is the one by Sirin Labs. They have created a cell phone that is designed to interact with the blockchain. It comes fully equipped with cold storage wallets and is built on a software design with security for the blockchain in mind.
@broncnutz what do you think of this tech? I posted a blog about it earlier in the week.

https://steemit.com/cellphone/@broncofan99/the-next-generation-of-cell-phone-a-crypto-junkies-dream-siren-labs