I have to say, this mod is truly outstanding. I've played a lot of Factorio, and often the end game feels prolonged, especially with mods that add extensive end-game content. This mod, however, breathes new life into the gameplay, reducing the monotony of the grind

Considering there are mods that utilize different surfaces for various planets with unique resources, it might be beneficial to have separate networks for each surface. Currently, it seems all surfaces share one network. A toggle to differentiate these networks would be a great feature or if some like leave it as one network for each surface.

Some example of mods that have different surfaces/Planets

https://mods.factorio.com/mod/space-exploration
https://mods.factorio.com/mod/planetorio-exploration

Main reason I use this mod is just for transferring materials between surfaces.

Copied my response on github:

Agree it would be nice and definitely needs to be behind a toggle since there are some use cases where players don't want to share items between layers.

There's some complexity in handling changes between multi <-> single surface storage but risks can be mitigated by some careful testing.