The Dark Knight had him retire more or less the Batman identity, to go on in the underground as Bruce Wayne (Although this was somewhat contradicted by it's sequel, nevertheless ...)

Kingdom Come showed Bruce having to wear robotic prosthetics to remain active, while Clark showed a little grey and Diana remaining eternally youthful.

Then we have JB's Generations where Bruce and Clark live at least another 300 years with little aging and plenty of action yet to come.

Then we have Batman Beyond where he is in his 90s mentoring his successor, who turns out to be genetically related to him.

Then I come across the (New 52) Detective # 27 where we learn that Bruce determined that 27 years is the expected range of active duty The Batman can effectively sustain and decides to clone imself in successive generations. Each generation taking the oath in a sort of The Phantom fashion.

Is it that fans/turned pros cannot bear the notion that a bullet will cut down Bruce in his prime?

Anyway, I prefer the Generations angle that Bruce and Clark conclude their respective missions on Earth anf then get a long, long, active "retirement".

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I think it is more the point that if you want to write a future Batman story, you actually want to have Batman in it. Killing him off when he's young kind of defeats the purpose.

Batman #300 had him embark on one final case taking down a criminal syndicate alongside an adult Robin before deciding whether or not to take up a citizens group on their request that he run for governor.

The Earth-2 Batman became Police Commissioner, married Selina Kyle, raised a daughter to adulthood, and was finally killed when a small-time criminal seeking revenge was given mystical powers by an enemy of the JSA's.

Neil Gaiman wrote "Whatever Happened to the Caped Crusader," which posits that following his death, Bruce Wayne will be offered a choice of what he wishes to do next and will elect to be be reborn to continue the fight against crime over and over again.

There was also, as I recall, a 1991 annual set in the future during the awful "Armageddon 2001" crossover, written by Louise Simonson in which Bruce Wayne requires an exoskeleton to get around and has turned Wayne Manor into a hospital years before Kingdom Come.

Another annual from that year had Batman escape from prison with the help of Anarky after being convicted of the murder of the Penguin, a crime of which he erroneously believed himself to be guilty.

The graphic novel "Batman: Digital Justice" showed a future where the Batman created a cyberspace simulacrum of himself to continue the fight against injustice past his death.

And there are also, of course, those Imaginary Stories written by Alfred which show Batman happily retired, married to Kathy Kane while their son, Bruce Wayne Jr., fights crime as Robin II alongside Dick Grayson, who has taken over as Batman II. Remarkably, the Joker is shown to have reformed and is a pal of the family who despises the crimes being committed by his son, Joker II.

A small number of Worlds Finest stories also posit a happy retirement from crime-fighting for the Caped Crusader and Superman while successors take up the mantle. Usually the heroes have kids who are up to one sort of mischief or another.

Batman is a remarkable character in that he is, despite his great training and mastery of what he does, mortal, thus serving as a sort of conscience to the rest of the super-hero community and remaining in some ways far more relatable to the rest of us. Captain America serves much the same purpose over at Marvel. Everyone else may enjoy superhuman physiques, enhanced lifespans, perhaps even live forever, but these two especially are "just folks" like those the rest of the heroes strive to protect and will inevitably meet their end in much the same way the rest of us will. Cap has already lived beyond his allotted span through a strange twist of fate, thus putting him into a future-world in which most of the people he knew have already aged or passed away.

I think it may have been Detective #500 in which Batman muses about some small-time crime he's stopping being a reminder of his career's beginning and its probable end. That sounds right, but then again, these are comic books and somehow, something always happens next... :-)

Then I come across the (New 52) Detective # 27 where we learn that Bruce determined that 27 years is the expected range of active duty The Batman can effectively sustain and decides to clone imself in successive generations. Each generation taking the oath in a sort of The Phantom fashion.

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Clone himself? That seems absurdly egomaniacal. Hand-training successors I can see; willfully creating new human beings solely for the purpose of furthering his mission puts him squarely in the mad scientist category.