The upside of this is that brute-force hacking will be much harder.
The downside is that many people are going to start writing their too-complicated-to-remember passwords down, and that will lead to its own problems.
But it sounds like this is a don't let perfect be the enemy of good solutions.
That said, given the choice, I'd rather have a remember-able password and have to 2 factor auth using google authenticator every time I log in. Perhaps at some point in the future you can let user choose which they'd prefer?
Writing it down is the least of the problems. The problem is now going to be keyloggers and obvious backdoors. How will they type in a password without hackers capturing it? SQRL and other methods can bypass that but then their smart phones would have to be secure and they probably aren't always secure.
In the end we have to access that people are going to be hacked no matter what and have good disaster recovery procedures.