What is the best way to do this, and what's the best way of ensuring a backup?
How do you currently store your coins
thanks in advance for any inputs
The best way to store bitcoins is with hardware wallet and you can easily download it. And of course for backing up just make sure you got a proper storage of that wallet so that whenever you want to get it, you can have it easily. Online wallets are risky but if you do trust them go for it, just make sure you are aware of what can happen to them anytime.
Also because it is more safer than the online wallet, because the online wallet is so vulnerable to hacker because of the internet, and we all know that everything is possible in our technology nowadays, and compare to the hardware wallet, hackers needs to get your wallet physically, for them to hack your wallet and it's much pretty reassuring because there is a lot of hackers that wants money, that is why we have to be more extra careful about our bitcoins.
I don't think that online wallet are risky because if you know how to manage your online account and you know how to secure your account then there is nothing to worry about. Just use a strong password and a separate email with strong password also and don't forget to turn on the 2 factor authentication in the website so you will be more secure.
You're right about the importance of the strong password and the 2FA and etc, the problem is not the hackers. The real risk is:
Just imagine, that you have your hard earned 2-3 or even more BTCs in your web wallet (means you have an account at a wallet service provider's website, and you don't have the private key, just an account, this is an online wallet). If the wallet provider goes down (closes the site, goes bankrupcy, etc.) then you will lose your BTCs.
If you have a hardware wallet or an offline wallet on your PC or laptop, you are in control of your private key (recovery seed, or any other backup method), so you don't depend on an untrustable party.
Web wallets are comfortable but risky, offline and hardware wallets are more secure but less comfortable.