So no this is not safe. Once ypu have a system it is easier to crack because if someone has 2 or more of your passwords they can work out there is a system and it’d make it much easier to crack others if they’re determined.

It is unlikely that someone random would specifically target a person and systematically try and crack their passwords. If that were to happen it’d most likely he someone they know. So while the passwords are definitely flawed it may not be something that anyone takes the time to exploit. But you can never say never.

The best way to manage passwords probably remains a secure password manager and randomly generated series of characters for each site. If its truly random then there are no shortcuts and every single password stands independently. The password manager gets round the issue of memorising them.