1
+ nice effects and you have a light source
-the render does not blend
-there is no sense of direction or flow
-text does not really fit in
-no focal point
2
+ the render is moderately blended
- the render is too sharpened
- the canvas is too big
3
+i can make out focal point
+i like the placement of the lower c4ds
-the render is blurred out way too much
-the smudging in the background (might be wrong) does not really fit in
i think that you need to look at some tutorials to help you improve. Also you should visualize what you want your sig to look like before you start. I don't really own gimp so i cant give tips on that front. Another thing is that the bigger the canvas size, the more work you need to put in.
why not get Photoshop. if you cant buy it....pirate