Barely anyone uses these ICQ AIM MSN YIM oddies. Maybe replace them with steam, skype, teamspeak, whatevers or simply allow us to create our own? (exampleish: my sig)
And the maximum characters for the signature is way too low. I'd suggest bumping it up way way high, like 1000 or 2555 or just removing the limit entirely. My current signature alone leaves me with 12 more characters left to work with.