It depends on what the site that has the password is.
Does it have any valuable information stored? Credit card info, etc?
If it's just a forum... yes, it's excessive.
But.
Use a password manager (I use LastPass, and can recommend it), and use it for everything. It will make a password as complicated as the site needs, and all you need to do is remember the main password manager password. I use it for everything that needs a password, except super high-risk things like my bank login. For those, I have my own, strong, complex password.
--Gray