Stealth sucked, but it seems like only the well required it, since it's unlikely you'll know the trick to bypass it there. I think the DLC would be improved by switching the slides for Starlit Cove and Shrouded Woodlands so that you learn about being dead to bypass the alarms, allowing you to skip the stealth entirely.
Also, I wish the game were more clear about the end of the DLC, since I didn't realize I had finished at first. I did really enjoy meeting the prisoner and showing him the results of his action.
Also, the changes to the main ending were pretty nice-- love that the prisoner being present causes a new race of secretive creatures in the next universe.