It shouldn't be too hard to put together a game along the lines of Knights of the Old Republic using the Mass Effect engine right?
Well, I don't know exactly how well the ME engine holds up in turn based gameplay, but I'd guess whatever engine they used for DA:O would be perfect for a new KotoR game. Now, I doubt they will use that setting as they already have ToR establishing that. Maybe a "current" Star Wars universe RPG. Taking place after Episode VI, but before Episode VII. Perhaps something from the expanded universe like from the Old, old times before ToR.
The gameplay is easy. The dialog, story, and atmosphere are what really needs to be done well. ToR was good in those aspects, but being an MMO, it obviously lacked the real epic story that Star Wars encompasses. Episodes 1-6 follow the rise and fall and inevitable rise through his son of Anakin. KOTOR 1 and 2 followed the rise (and if you chose, fall) of the Republic, as well as your character, through the story. ToR just didn't have that. Granted I only finished a couple of the story lines.