I also use 1Password and echo Richard's Rave.
I spent a good deal of time researching when I decided we needed to move from a text list to an actual password manager, and 1Password was the clear choice. It's updated frequently, and the developers appear to be responsive to feature requests and bug reports.
On the Mac, it's extremely useful because of the 1Password Safari plugin. So if 1Password is unlocked, when you navigate to a site that requires a password, say a banking site, 1Password knows you're there and it's a simple click on the 1Password plugin icon and a return to enter the password.
It's not perfect, of course. Sometimes 1Password is too eager to set up a new entry for you. And sometimes when it sets up a new entry, it plucks the user ID entry from the wrong field in the web page, so you may need to tinker with the entry after it's set up. 1Password will offer a variety of passwords (more below) but then I'm always worried about the password getting lost before the entry is set up. That's actually never happened to me, but I think they could make the process a little more obvious. I always check a new entry after setting it up.
Because I found too many web sites that didn't function with auto login, I set all my 1Password entries to just paste in the password and I then click the Log In button myself. A few sites show the password field well before it's functional, and you may need to be aware of that.
I don't know any way to get Safari/Keychain to stop trying to present you with a new password for a site, and you normally don't want to mix where you keep passwords.
On iOS, you have 1Password as an app, but no plugin for Safari. So you may have to copy and paste or drag and drop. That's much easier now in iOS 11.
And it's really annoying to deal with passwords on the Apple TV. For those passwords, you probably want to make them shorter and very easy to enter with the Apple TV remote.
As in all things security, your master password for 1Password should be strong. Many sites continue to insist on nonsense about passwords. Length is the key to strength, not numbers or symbols. 1Password offers word-based passwords as well as the more traditional mixed ones some sites insist on.
So choose a longish master password that's easy to memorize and type. Write it down and transmit or store a copy. You'll have to enter it every time you use 1Password in iOS and at least every couple of days on the Mac.