First, I did not know you could boolean radial lights together....   BUT if you could here is a suggestion...  I hope I did not misunderstand.... otherwise please excuse me.....

Choose a radial light and click on the 'E'   function you'll go to the lights lab

There is a function in the lights lab under render option called Visible objects  make sure it is "on" and choose "on" for  Volume  as well.... now bring up the intensity amount ( 80) and you'll see that the radial light turns into a sun when you render it....

Now imagine if you could boolean several radials lights together.....  and play with color and intensities....  am I making sense ......

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