Thank you very much!
Yes, I was also thinking of making it more similar to Portal in which you have two fire buttons with two different portals ultimately linking them. For now I stuck with the "1 shot link" in which you use yourself as a carrier.
Would changing the background music help indicating your current state? Currently it does affect the sound you hear when you hit your gun, and your own animation and movement speed. I will look into creating some GUI element.