Actually Biggs, the umbrella - especially it's color, puts something into the picture that's missing if I cover it up with my hand. It becomes more ... standard. The bright color from the umbrella reflects that it is a bright sunny day, and it helps to give the background some scale - it even makes the oof lights further in the background ... um, bokier. And the similarity of the shape to the bottle in her hand makes this nice pie shaped composition. I vote keep the umbrella.
ps - you have a very cool avatar. I forget, what do you want us to call you?
Good observations Chris but you forgot one, the umbrella has the same lean angle as the bottle. What can I say, I was just trying to get the girl out of the center of the image and failed to see all the valid points you made.