I turned off Signatures just to check how the forums look without any signatures.
To tell you my personal experience and truth, I didn't like the Page without any signatures. Its the signatures that make the Page look a bit colorful and attractive.
However i do agree that the Posts should be constructive and interesting too.
It depends on personal favorites, and your experience in the forum. I have not joined the forum for too long, just around two years. However, I read that grand-father forum members mentioned about the period in which the forum did not have signature. They called it as a pure period of the forum, in which no signature, no spam, and maybe no or very less scams. For those guys, I thought they support the approach to bring the forum back to the pure period, and theymos mentioned they if merit system failed to control spammers, he might actually disable all signature industry.
Fortunately, as we all witnessed, merit system has worked perfectly, so theymos might not disable all signature. Yobit signature is the first one I have ever seen theymos step in and disable it globally in the forum, in 60 days.