EDIT: I was a little late, but this paragraph was for Vividwire
A good rule of thumb is that if you have to question yourself about it, chances are you didn't do a good enough job or in your case you're doing something wrong. But I'll let the administrative team answer your question.

On Topic:
It wouldn't really bother me with the images, however I really like my little PReader . And as Salathe mentioned, my signature is a reflection of me like any signature should be. Just like clothes. See, I go to one of the few (probably only) public schools in my state that allows us to wear whatever we want (within reason); so I guess you could say I know from experience or that I'm a little biased.

I think we should apply more rules on the images, however we shouldn't completely restrict them.