Excellent concept, good attempt, far too short
Some ideas for making it longer.....
1) Expand the mission intel so that its more extensive, if you add a bit of a story you can really draw people into it and they will give you endless suggestions for improvement that you can use to create your own frontpage masterpiece.
2) Add more options so that the player can see descriptions of the characters surroundings, maybe they have to do this to avoid a trap or get a key.
3) Really expand the mission itself......even a ghost has to figure out how to reach a facility since its in territory controlled by the enemy while their cloaked as they have a limited amount of energy for their suit and they have to avoid detection, so make infiltration a part of the mission itself. The next challenge is entering the facility, the doors to a military command center are not just going to be open to everyone, so how does the ghost and protoss enter?
4) Add some graphical details to it......this place probably wouldn't be in pristine condition, the protoss might have had to break down doors or walls to get to where they are in the facility. Add some blood to the the places where the enemy is shot, you could even use that time to add a little scene in which you see the bullet going from the gun to the spot on the enemy, ghosts were known to have superior physical and mental training compared to other terrains so an adrenaline rush for slowdown (matrix effect?) wouldn't be out of the question if they had to hit a target multiple times in a short time span like with the first zealot in this submission.