It can become a problem once it gets into the yellow zone, but that's usually when people use over-sized pics, etc. If you were to edit your sig, you might consider using the text size code to reduce the text size a notch and that would shrink it somewhat
Thanks for asking!!
Amandie we don't actively search out large signatures, but we edit or delete if we see them. We don't see them all
We usually try to trim them first instead of deleting them. We also receive complaints about signatures and that often brings them to our attention as well.