lol how the software handles or i should say doesnt handle signatures is a definite problem atm.. I went from spending most my time fixing my vB4 forum to spending most of my time removing ridiculously over sized sigs on XF.. It really is one thing that drives me crazy.
It's not a problem on my vB forums and won't be a problem on forums in general since the forum owner would set the rules.
When someone has a problem with a sig on my vB3 forum other members generally let that person know and it's corrected.
It's usually corrected before I even notice it.
Hobby forums can get away with peer to peer monitoring.
It's one of the few things that really destroy what this forum tried to achieve (focus on content) and I have to say with it's generous rules (which there aren't any) the focus is always on the signature rather than content.
Personally I think it's ridiculous at some of the signatures allowed on here. Quite a few of them are longer than the posts themselves.
One of the problems members here have is reducing the size of their signature because of the limitations in the CMS at the moment, I tried to reduce the size of my font a few times, but when I did it was so tiny that it did not work.