The easiest way I find to make text work is to throw it in a clipping mask, and find something that looks right and stands out, while going with the flow of the sig instead of interupting it.

Also don't be afraid to mess around with the brushes for smudging, try getting it to go into a specific direction to create flow within the signature.
Another thing I've learn't from others is to not go with a full border, this causes the space of the sig to enclose and makes it seem like the image just ends, whereas if their were cinema borders (top and bottom) it allows the eye to think that it goes outside of what is shown .
Keep trying and it's good to see your dedicated to becoming better