Well, I just played the mission, and it definitely shows promise. You certainly know your way around FRED, and you know how to put together a mission. The only thing I would change is balance: the mission is a bit crazy for five minutes and then it suddenly stops.
A three-star mission is nothing to sneeze at; think of it as taking an AP test in high school: three stars is "well done"; four stars is "excellent"; five is "outstanding". It's a good mission and it's better than average. I'd say it's even better than some of the newbie missions that have been released on HLP.

Why not try out
FRED Academy? You can make some missions for some campaigns that are in active development and people will critique them.