This includes setting ship destinations, managing routes, sending messages, viewing planets, transporting cargo, and so forth. At a Glance window allows for powerful views of all planets and ships in an empire. This is because you can typically see all that happens and control everything at any distance, great or small. Careful emperors can set up communications networks which allow for instant communications across great expanses of space. This is very easy to explain.
Technology is localized.
Increase your weapons technology at System A, and you'll need to transfer it to System B if there's a construction facility there that needs it. There are facilities in the game for helping to automate technology transfer, but it is another strategic element of the game. The first planet you own is only your home world because that is where the Emperor is. The location of the Emperor determines where orders emanate from, and where updates from ships and planets are sent. The name of the game says it all.