No matter the password strength, I check my bank accounts online once or twice a day. 24 hours will not pass before I can respond to foul play. I think that's better than having a super strong password and checking bank accounts only once a week.

By the way, I do need a system that allows me to memorize, even though I will also keep a password vault program. Every now and then I'll find myself somewhere with nothing but an Internet connection on a random computer. I need my password to be in my brain at that moment. Thus, I need to memorize at least the important passwords.