Me thinks you are making too much of the "Have-A-String-Password-Or-All-Your-Info-Will-Be-Stolen" syndrome.
You really only need two passwords:
1. For your device (iMac, iPhone, iPad, etc., etc.)
2. For your password manager (1Password, LastPass, even Keychain)
First, I assume you have your device setup to require your password at every start up (or even Sleep). If not, why not?
Do not have automatic logon enabled without much consideration (main user is an elderly person, etc.).
Second never use "Apple" in conjunction with the name of the password for your apple devices. In other words, don't think of the password for your Mac as an "Apple password". It is simply your "Mac Password", etc. It is not an "Apple" password. Apple has no idea what that password is nor do they have it stored anywhere in the world. It is simply needed to prevent a thief, nosey neighbor, wayward child, etc. from turning on your Mac (iPhone, ...).
Third, unless you live in a high crime area
AND your device is brand new
AND/OR you have important government data on it, your favorite/first pet's name should be fine. Perhaps throw in some numbers like the year your significant other was born. Something like "19Algon49quin!".
Fourth, iTines, App Store, ApplePay, AppleID and other resources controlled by Apple, require an "Apple ID". It uses the email address with ".mac", ".me", "icloud.com" or whatever was used when you bought your first Apple device. It is used to edit you info at Apple. It is simply another password email combination like every other email/password pair used at almost every site/company/etc.. That is the only "Apple Password" you have. It is completely separate from any device's password and is not needed to run any of them.
Fifth, write down at least these two passwords and "hide" them in your freezer! After a few trips to your freezer, you will have committed these two passwords to memory.
Now your only worry about passwords will be praying that no one steals both your Apple device
AND your refrigerator!
Lastly (
I thought we'd never get here!), buy a dependable password manager, learn how to use it and use it religiously. I use 1Password to store all my passwords and hundreds of other important data, including refrigerator repair services.
