I don't see what the problem is with premise of this episode but SPN fans are not happy.
I will hold judgement until I see the episode. Here is a brief description from Supernatural TV. To be honest, I think somebody screwed up this description a bit.
We’re still a little more than three weeks away from the return of new episodes of Supernatural, but here’s the official description for the big April 15 return, titled “My Heart Will Go On.” And yes, Titanic plays a major role in the episode. Keep reading for the descriiption:
“After Balthazar changes history and keeps the Titanic from sinking, Fate intervenes and begins killing those that would have died on the ship. Castiel tells Sam and Dean that Fate is very upset with the two of them and the only way they can stay alive is to kill her. “
Some pics of the return from the dead, Ellen.