Hi Sammy,
nice post, however i think, that your passwords are very short for nowadays computers and password generators.

In general, longer passwords means much better security (even without special characters).
So as a suggestion, i'd extend your pass formula to some constant suffix/prefix (8 alphanum characters), which would then hopefully make it 100% attack proof.

Anyway, log files and some nice ban utility on your server is also good to have. I use fail2ban on my servers and it works see more very nicely...

have a nice day..