I generally do not store my private keys from wallets in any electronic devices that are connected to the Internet. One of the safest ways is to keep your private keys on paper. After all, the reason for the loss of our cryptocurrencies in wallets is not only our mistakes, but also hacking of our email addresses. In them, as a rule, we keep information about our various passwords, private keys, hackers are also very actively interested in our backup. If there is a need to store private keys on devices, then it is better to change at least one or several symbols in them beforehand.
actually what you are doing, including for me, is creating its own difficulties even though it is quite safe to do. because if we put it on paper, the fear is, if the paper we use gets hit by something and can't be seen anymore and it will be confusing.
actually if I prefer not to use a private key but save the *.JSON file and put it in a yahoo email address by creating a separate folder and your yahoo email address is connected to an iPhone device which every time you open an email address asking for authorization by just clicking yes on iPhone . this is the safest thing that can be used.
or if you can, the *.JSON file is stored on a flash disk which does seem outdated but is one of the most effective to use because it is more difficult for other people to reach.
why it's good to use *.JSON files instead of private keys, obviously *.JSON files are safer because they need a password to open them, whereas private keys can be used directly.