I love the picture, it's very sharp =) I'd like to add that even though people *prefer* longer and thinner signatures, yours is within the guidelines set for it, so if you don't want to change it you don't have to. I can imagine it would definatly give it a different look if you'd cut off the top of the picture or so to get it less high
Text wise, to be honest I didn't even realise there was text untill it got pointed out. A different colour might help it, I agree with the orange colour to match the fish. Or perhaps get the line of text in the picture itself rather than under it.