This is the final word.
1: Uploaded sig images will be less than 500x100pixel and 50kb.
2: Offsite linked sig images should be the same.
Breaches will have sigs deleted.
Admins will not be actively looking for breaches. However if one is noticed in the course of normal activity, it will be dealt with.
If this sig thing becomes more of an issue than it currently is, I'll turn the function off.
