Please be aware that if you are using the coats of arms in your signature, they need to conform to Org rules. The bit about signatures is as follows:

The rules for signature pictures are:

* 10,240 bytes max.
* no sound.
* max 500 pixels wide, max 150 pixels high.
I'm not too concerned about the file size aspect, but all images used in sigs should at a minimum be run through a web optimization program to compress them down as much as possible. Using raw .png files is not a good method. In addition, the dimensions (500x150 max) do generally need to be complied with, particularly the height. Lots of extra high signatures can make threads difficult to read.