GFX Signature/ Advice

Hey i just downloaded Gimp and designed these two signatures. Are they any good and how could i improve them.

Bear in mind these are my first signatures. The name Enixia is my xbox live name so just ignore
And also do they fit the requiremets for Sythes rules? Are they too big?

 

These are good but they could be better : / good job

 

yes there great but... there too big try 400by150 and there plain add render and stuff like that

 

Pretty cool. Below is my first attempt, about to have another go at it. I sucked pretty bad :X