the "rays" i was picturing could be fading from very transparent, out to nothing at all, two shades of warm color... or even the radial you already have, but several pie slices alternating on and off & then set to white or light yellow, with translucency... so it creates two tones with what you already have, and some lines going out from the center, between each pie slice...
here is something I grabbed quick from a banner I did.. didn't bother to change color or make it fade... but just to explain what kind on sun rays i was thinking of...