As title says, it would be great for modpack makers to add dimensions where their skybox would be replaced with stellar view skybox. As well as to control the rendering of planets on the skybox

Actually already done, will be available when version 0.3 releases. The whole system is being rewritten to be resourcepack-based, allowing anyone with some basic knowledge of how resourcepacks work to change anything they like.

Ah, that's great, can't wait for the next update then :)

I had a similar idea, an ability to choose an Y level (for each dimension) at which the custom sky will start to fade in, and another higher Y level where the custom sky is fully visible.

this shoulda been closed by now

so, @User4716, you're talking like how the skybox darkens when you go underground, right? That's a good idea.

@User4716 or @Noobly-Walker make that into a new issue please. Sounds like a cool idea if I understand correctly and it would be a shame to forget about it just because it got buried in a completed issue.