Good day, just want to share my experience,
I am using 2fa as my security in my emails and exchange accounts, so one day I nearly lost my phone and that phone holds majority of my pins, 2fa, etc. so I thought I lost all, luckily I found the phone. So now I'm thinking of buying an extra phone for backup. What else do you recommend for backup?
For me even if you have just one smart phone you can make a back up you can write in the note book, on paper and in your diary and keep it important to backing up your Private key or QR code and Gmail. So even if you still have the phone you can still access it using a laptop or computer you will not worry that others might get your bitcoin. But your plan is good too i'm just try to give you some idea how to secured your data. good luck!