Is it possible to change your character's class (Tactical/ Engineer/Science) with a re-train? If not, is there any way to do it in or out of game? I have found myself not quite liking the tactical class with my foremost character and I want to change him to an engineer (I have played an engineer klingon and loved it). I don't want to "fish" around for a good character, I already know that I want to be an engineer, I just did not know that when I first started. I have spent a lot of time with this character and I really don't want to start a new character and have all that time wasted.
You have to start over, but consider this an opportunity. Now that you know what traits do what, and what races are good at what, you'll be able to make a better engineer than if you had just switched the class of your old character.