I think positioning your daughter in the middle was just the right choice in this case. Converging lines of the pathway lead the viewer right to the main subject, making her the center of attention. That is not to say that you shouldn't experiment with different angles. In the end the right composition is the one YOU think looks good. Nice job catching that ball in mid-air too. My suggestion would be to crouch next time to get down to your subject's level which usually makes for a more personal picture. Also use your flash in harsh sunlight to get rid of those shadows on the face, and make it more evenly illuminated. Finally, I would crop out the somewhat distracting background at the top of the picture. Hope it's not too much critique, because overall this image is very lovely :-)