Inappropriate isn't an issue, it's just the sheer size of some signatures. Mine used to be a lot larger, but I toned it down. I'm considering doing so again by getting rid of the pictures.

At my large resolution, Cooba and Derviative's signature sizes are equally large, but when I go to a smaller resolution, Cooba's remains relativly large Tub's grows massivly larger. If we try to enforce a size limit on posts, what may appear offensive and huge to one person may be rediculously small to another. I'd suggest the best course of action would be to disable image codes on sigs and turn on avatars with a size limit of around 80x80.