The text should be smaller, and moved toward the focal--his face-- and I see some big squares on the right side, that doesn't look good in my opinion. The tag in general looks smokey, and I think you've got a lot of potential.
1. Agreement that it's smokey. 2. Can barely see the render. The smoke all over the render seems to make it hard to see, and it looks too light. 3. Agreement with the text. 4. Smoke is too bright? 5. Dark background tends to make Itachi's hair blend into the shadows. xD 6. Random lines!? It indeed, ruins the signature, like what Lemuralia said.