The color scheme seems really random, and the bagckground looks pretty flat. Idk, it's a descent sig but you could work on a lot of things.
Old brushing style sig Work on depth, it looks really flat. Lighting is off. Colors look like poo (literally, don't try to put brown and green together). Text needs work. Try to blend in focal better. More foreground effects are needed. Sorry for being so harsh :[ Try some of the tuts to get a feel for theses elements :]