Possibly the 'death' mechanic institutes some kind of set back. Something that is party wide, possibly coming into play only at the final act. At least at that point it would be a case of 'we all lose together' so that players are not left sitting at the table bored.

In conjunction with that or separately you could have a stable of NPC's that have the 'job' of dying in place of the party members at least for the first few deaths. Their scream draws the attention of the stalking monster so they grab him first, or she pushes you out of the way of the trap and gets impaled instead of you. That kind of thing. Something like that would emphasize the high mortality but also let players stay around longer, at least until the NPC's are gone...