Try changing the transparency of the atmosphere, the graininess of the atmosphere as you might observe is caused by the fact images can’t have infinite resolution. You may also want to change the color but that’s not for certain!
Hope this helps
edit: as a disclaimer, the atmosphere is not meant to be used as the atmosphere when on the planet, only when observing far enough from the globe. If the provided recommendations don’t fit to your expectation, I’d recommend you transition between using Roblox in-built atmosphere for the sky when on the ground and my atmosphere for planets when you’ve reached some distance from the globe.