[Suicide Junkie]

Another option would be to use the map editor.
Then you can add 4 times more warppoints to each system, and have the new ones all dump ships (one way) into black hole systems.

It really would be a warppoint, so ships would try to explore it.

The problem with that is once one ship has been lost to the hole, you will know where all the other doom WPs go...
Perhaps make a whole bunch of doom systems for your fake warppoints to go to.