No thanks. The universe and.travel within it currently fits (very loosely) into physics as we understand it so that it doesn't take a huge suspension of disbelief. Having a "portable wormhole" or similar would just make most of the galaxy superfluous. Where's the challenge in getting a nebula, or Sag A, or Hutton station etc if you can just fast travel there? There's plenty of places you can travel to ludicrously quickly already.