While I appreciate the input, no.
This is a discussion board. So long as the threads fall under the TOS and aren't straight up SPAM, they stay where they are and let nature take it's course. If it's not worth discussing, it will fall out of the first page quickly and not be an issue. If people are responding, it's clear that it's "worth" discussing, and that includes topics that have already been done before. For example, there are several threads on bringing up Pat Devlin, discussing it to death, yet a new one seems to do just fine.
As for signatures, you can turn those off in your general settings. Go to your UserCP, then click on General Settings on the left. Scroll down and under "Thread Display Options" you can choose whether to see signatures, avatars, and/or images. You can adjust a lot of the viewer setting there.
Further, if you wanted it plain-janed up even more, you can change the layout option of the forum by clicking on the scroll bar at the bottom left of this page (the very bottom). I suggest "Mobile" which is super-boring.