Horses for courses I guess...
People put too much stock in paranoia surrounding passwords, a person is as likely to guess a random unrememberable password as they are to guess the ones which I use. Some kind of algorythm to guess password is unlikely to get access to make the millions of guesses it would take to get them also. And, most importantly it is extremely unlikely that someone would even want to invest the time and effort to gain access to just your information using your username and password. Most security breaches and issues that jeapodise your personal information happen at a higher level.
A password and/or password security system is never perfect, i choose to make it difficult enough whilst still remembering it and having a different password for each site. The benefits gained by using a random system and password security system like last pass sre negigible considering the fact that you're adding another avenue for people to access the passwords.
You are a number in a sea of information, anyone who would need your password to access your personal information would not have the nouse to crack it.