Hello @SEANarchy, and welcome to the forum!
I want to recommend to you a few bundles. You unfortunately need to create an account for the first one on a platform called DeviantArt, but registration is free, and you don’t have to buy anything with them. By the way, beware of uploading art to them, you’ll more or less giving away your rights on your own works!
So, and now to the bundle, it is meant for space paintings, and you may know space means darkness and light, and here this bundle shines in my eyes, and of course it offers nebulae, I guess you will want to make use of them …
Maybe you’ll like it like I do:
https://www.deviantart.com/iforce73/art/Universe-Environments-Lite-Version-856958730
By the way, if you like that bundle, it is a light version, you can get the full package for $5 at GumRoad, a link to it can be found on the linked DA site.
This one is a preview of a bigger bundle I’m preparing, it is also from iForce73 and this is part of his Environment Brushes and Forest Vegetation 3 set of resources which was made for Krita 4.x, the one I offer for download is now Krita 5 capable:
I’ll remove this link very probably at the beginning of next year, as I said it is only part of a preview, but it works for me.
And then I’ll like to suggest you this huge general purpose bundle which offers brushes for clouds, for light, and so much more:
And here you’ll find a clouds-only bundle:
Michelist