 11.19.19  9:07 pm if you implemented the sky as a world node setup then you could make it in a file then save that file (along with any other material or world node presets) as the default startup file, then every new file you make after that will have your presets in it
i did that but it disappeared after a day .... also with the amount of items and objects i would like to have saved, i would think that file would get pretty huge and slow to start up?