Use of a "dead" system.

[Alneyan]

It only acts as a buffer indeed, by warning you of invading fleets (putting a spy satellite or three within the system would be a good idea; one to "engage" the fleet and get their designs, the rest to do the proper spying). Other than that, its uses are as a trap.

For example, such systems are *very* interesting if you plan to use a Star Destroyer as a "don't move any further" scheme. If they enter that empty system, their whole fleet is doomed. Likewise, you may be able to shut down the wormholes leading to this system once the enemy fleet has warped in, effectively trapping the fleet in that pointless system. Compared to a system with planets, an empty system has only one advantage in this field: you lose nothing yourself, whereas blowing up one of your inhabited systems can be painful.

Nebulaes and blackholes have more direct uses though, if you can pull such strategies out (a nebulae helps to hide you, as you cannot be detected in red nebulaes, and blackholes might allow you some fun with Ionic Dispersers), but that would be another story.