@Charlaquin - I think you are seriously undervaluing the notion of character death as an "inconvenient nuisance".
For my group, when I've done more plot heavy games and taken death off the table, the goal of the game is not "to struggle against the restrictions the rules place in the way of that victory condition". The goal of the game is far more about collaborative story telling. Which doesn't mean that you have constant victory. No, when I took death off the table, the players became far more focused on their characters, adding depth and personality to those characters, because they knew that they wouldn't randomly be forced to make an entirely new character and leave all that work behind.
There's a very good reason that when you get into more narrative based games (sorry for the Forge term) that character death becomes less and less likely. Concerns about "fairness" or that sort of thing go straight out the window. We're not "fair" to our characters. We want to put those characters through as much of a wringer as possible.
As an example, I ran an SF campaign using the (SA) Sufficiently Advanced system some years ago. With SA, the characters are more or less immune to death. It's possible, I suppose, but, extraordinarily unlikely. But, the scenarios we played were all focused on making choices that had very philosophical impacts. For example, one scenario had an invention (a small toy) that definitively proved that the universe is deterministic. The space station where the toy was invented saw mass suicides as people could not take the idea that their choices in the universe had no meaning. The PC's are called in to determine if the toy is actually, in fact, real, and how to stop these suicides. There was no chance of their characters being killed. They could choose to kill their own character, but, no chance of random death.
Yet it was a fascinating scenario. Seeing how the players got into it, dealt with it and then finally resolved the situation was something that I've kept with me for years. Loved it.
So, for me, I've seen what happens when you simply take death on the table, and, IMO, it's almost always been a positive result. I've never seen players take the game less seriously just because they knew their character couldn't die.