Why not make any raids, future and now, to have a harder difficulty exclusively for those with dlc and have another go to get weapons with the new damage? That seems fair to me and an easy fix. Those without dlc enjoy the raid for what it is and get the drops as they are now while those with dlc can acquire new upgraded weapons all over again. It's just an idea and I know it would be unfair but this game is moving forward and why bother keeping a game if you don't get interested in dlc especially when there is so much more to come?