In all honesty, (at least my opinion) it'* not necessarily the file size of sig pics that can be annoying, but the overall size of it--for instance, on my 19" monitor, my signature takes up about 1.5 inches of vertical space (or something like 492 millimeters for people like Al)
On the other side of the spectrum, I have to scroll vertically just to see all of crazydriver'* signature (not trying to pick on you crazydriver, just happens that your sig is in this thread, and makes a easy to see example)
Maybe we need to put some sort of "height" restriction on sigs in general?
There'* at least a couple forums I frequent that have sig size restrictions--typically they ask that if you have 28 bajillion mods, make a banner-sized pic that links to your own webspace or something like that, or maybe say that it can be more than xx number of "lines" tall
Just my 2 cents worth
What resolution are you running on? You shoul be at least 1280X1024 with a 19". I run 1600X1200 and the pics are tiny for me.