I have already posted something similar in a thread which was simply a 'topic point', however I really do think it would be an amazing thing to be able to 'fall to the dark side' or be 'redeemed by the light' for characters. If there were story lines that allowed this development, I think it would be an outstanding addition to an already stellar (no pun intended) game experience!
Originally, I thought it WAS an option! When I first played, I created a Jedi Knight, and in the cave on Tython when you confront that first dark apprentice, one of the conversation options is 'can I join you?' So, naturally, I thought you had the ability to 'switch sides' if you wanted. I didn't choose that, I was being a true Jedi padawan and fiercly loyal, but I was surprised to find there was no option for it. Especially in a franchise (both film and books), that is rife with failures, corruption, hope and redemption. I mean really, if Vader could be saved.....
Some say it would be too complicated, but it could be an option that only unlocked at a certain point, or after so many Legacy points, or something. I don't know. It just seems like there is an epic opportunity for further story lines, deeper character development and entirely new missions, flashpoints and more.
Please, consider this as a real option? See what people think. Well, thanks for listening to my rant.