In all honesty classic Batman is the surperior Batman out of all their future iterations.
You see I really like the Killing Joke, it was an entriguing story with an ambiguous ending as to spark a very intention shitshow of opinions regarding as to whether or not Joker is made to go commit the die. If we exclude Watchmen for obvious reasons, then in my opinion, it can be considered Alan Moore's magnum opus.
But for as much as I love this, I have the same amount of contempt for it, for, according to my knowledge considering how I only read Batman Elseworlds and Oneshots (and a few issues of the original Detective Comics), it's where the "der sad and broken psycho" Batman originated from.
When I read through Detective Comics, when the OG Batman lost his parents, he didn't go all emo and bitch about it, he didnt spend every waking moment constantly haunted by his parent's death. No, he took the experience and made something heartwrenching into a motivator, he didn't want to fight crime out of spite for his parent's killer, he wanted to become a crimefighter as to ensure that what happened to him could happen to no-one else. Classical Batman is a story of a privileged person being motivated by a loss of those he cares for, and instead of giving into his grief, he tries his damndest to become an ideal, somebody to admire as a symbol for Justice, often at the expense of himself and things he could out of enjoyment, (not to mention the Wayne Foundation if my recollection of it being a Pre-Killing Joke thing are correct).
Post-Killing Joke is just a Broken man taking out his rage on criminals, he may care about being a model to other's, but he lets his rage and grief consume him to a point in which he appears as "lol der edgy hedgy".
Ultimately, whilst you could make the argument that their core traits are fundamentally the same and that these are two different ways to commonly deal with grief, the Post-Killing Joke Batman essentially becomes less Batman than he ever was and deserves his own seperate IP to transcend the "Pre-Killing Joke" era of Batman
TLDR: Pre-Killing Joke Batman became a superhero because he didn't want anyone else to go through what he went through, he didn't bear a personal vendetta against criminals, it was solely for the ensurance that the shit he went through didn't happen to other's. Post-Killing Joke Batman succumbed to pains of grief and coped with them by beating the shit out of criminals, whereas Pre supressed it, often at the expense of critical thinking and logical decisions.
P.S. a tad bit unrelated to my main point but I feel like Batman was intended to be a motivator of sorts to the privileged saying "you have something that other's don't, use what you have to help them and make them like YOU (with regards to circumstances and general wellbeing. NOT in terms of ideology, that's wen you get christiany) which is why I like Pre-Killing Joke Batman moreso than Post. So yeah, those are my bias. Personal love of Privileged peeps helping out those of less privilege.
(And yes, i'm fully aware that during the first two Batman-involved stories, he is seen maiming and killing shit, but that is induced per the writer being influenced by pulps, Post 1942 Batman but still Pre-Killing Joke is the one im referencing, im not saying the OGest OG batman, im talking about the "more OG than any future Batman stories can ever hope to be" Batman).
