It's hinted pretty strongly a number of places that the main goal is to get off the island. You can also tackle that a number of ways.
Maybe it's not the same for everyone but taking those smug bastards down a peg was reward enough for me in the keep. That being said, there is some lore stuff in the notes laying around, if you didn't read them I might suggest it. It's not going to blow your mind or anything but it sets up what I would assume are plot points down the line.
