I had an idea a couple of months ago about an antagonist to Batman. Even though it's a different character, the origins would make for a good alternate version of Batman IMO.
I would like to see an arc where Batman is put up against his sort-of-antithesis. Not Wrath; a new character that also has similar origins, but has different methods. Where Batman was a billionaire, this new character would be poverty-stricken. Where Batman had the best tutors in the world, the new character had whatever was in the public domain - Internet, encyclopedias, etc. Where Batman had the best martial arts masters, this character has only one who teaches him only one style. He also has to make do with whatever resources he can find, rather than being able to come up with new stuff. Despite all this, through sheer determination (much like Batman's), the new character is still on the same level as Batman. Because of his different upbringing and training to become a hero, this character would have different methods like being okay with killing (though not actively doing so such as, say, Jason Todd) and occasionally asserting that the ends can justify the means (i.e. breaking laws at times in order to serve the greater good).
So, you want Bane.