Thanks!
The coloured dots are in fact each a simple "Light Source".
I thought this gave me more freedom in placing and colouring them as stars/galaxies/planets or whatever.
And when I had one light tweaked to my liking I could leave it alone and get on with the next one without altering the sky as a whole.
Placing the light closer or farther away together with very small numbers in the starburst and bloom settings it is "easy" to achieve
different magnitudes of brightness and glow. And they render very fast, too.
It would help immensely if we had bloom or starburst per object or light.
Next step is to find out how to make some sort of larger nebula or milky way in the skies as separate objects.
I always seem to have difficulties to insert another layer into the skies or terrain or whatever without messing the whole thing up...
Gotta read up upon the Nebulae thread by Hannes from 2014.
Anyways, if anyone is interested to take a look I will post a scene file later.
Cheers, Klaus