Do you think this would increase the Potential Enjoyment Factor of a game?
By itself ? Not really. Depends on the rest of the game.
There have been many games with similar mechanics.
There was a recent roguelike i believe, seven...something, where you play as a member of a family, and if you die you switch over to the next member.
There was, of course, Omikron, where if you died, you took control of the first person to touch your corpse.
There is Demise, where you could get yourself killed or potentially obliterated, and if you wanted your characters back - you had to create new characters and go pick up the corpses to resurrect in town, or grind until they learned some high level magic.
There was that recent console game, where if you died - you could tell someone a code, which they entered on their end, and then go on to save your characters.
I am quite sure there have been more than one roguelike with characters than could go on after death as undead. Cant think of the names at the moment.
He travels to the site of Fred's death and causes Fred to be animated as a Zombie. The player can now resume the game with Fred...as a Zombie.