I'd like to see some sort of perspective in this shot, such as also incorporating the person flying the kite, or some trees, or just something else to situate the kite in the sky.
Yes, well, either some sort of perspective, as Bull Goose is suggesting, or a closer crop to lose all the dead space around the kite. Maybe cropping this horizontally would already do. For all in all the blue sky and colours of the kite look good!