I know there are wormholes as traversable gravity wells in sins1, but I think they could make an appearance in another manner in sins 2.  Either as random events that connect two or more planets or as tech that can be researched.

The tech would maybe create a wormhole in the target gravity well and then a random one elsewhere connecting distances gravity wells.  Or possibly created at the end of one phase lane so that when ships jump to the gravity well they end up going through the wormhole instead and ending up somewhere else.