I can’t offer any good advice, just take consolation in the fact that I have done some of the same, but likely worse. I try to switch to a new email, don’t fully migrate or close the old one, end up with a convoluted mess, end up just checking emails individually. I have protonmail, 4 gmails and a yahoo account. Yes yahoo. Part of that is sentimental, I signed up for it in 1998 and it’s hard to let go. I have a folder of email bookmarks and just right click ’open all in new tabs’ to check them. As for passwords, well, I wont talk about that. It’s not good but still not worst practices at least.