Why is there no Discworld!verse Batman?
Is it me or would this be the most amazing thing ever? And naturally, it wouldn't have to be Vimes-ian and but Vimes would go ballistic at the thought of a vigilante running around his city, hitting people over the head to make them talk. Batman's all about the gadgets but honestly, a little bit of imagination and that would solve that.
And the set-up! Oh God, the set-up!
We already know Sybil Vimes nee Ramkin is the richest woman in Ankh-Morpork and we know her family is one of the oldest. Bruce Wayne wanders back into Ankh-Morpork from god knows where he's been and the Waynes are up there with the Ramkins, close enough to be built into the fabric of the city. She knows everybody including Vetinari by his first name, she's a friendly soul like that, and Ankh-Morpork is made for an idiot in a costume to swing around the rooftops, fighting crime at night.
And Vimes, oh God, Vimes, who will be so fed-up with idiots, especially when other crazies start crawling out of the woodwork now that the Bat Man (read: Sacharissa with her deadly pen) has kicked things off.
Enter mild-mannered night-shift sergeant Gordon who has a sudden and inexplicable case of enough evidence to put down a couple of [insert tricky cases here]. Along with a butler who isn't an Igor and gives Willikens a run for his money.
And of course, Ankj-Morpork being Ankh-Morpork, everybody will have an opinion, whether they like him or hate him and in other news, Bruce Wayne is a charming if very brain-dead young man burning through the unlimited family money with parties and philanthropy and a cheesy grin that would set Vimes' teeth on edge except that there's something odd about Bruce Wayne and he's determined to get to the bottom of it. Even if Vetinari seems completely unconcerned and enigmatically knowing.
Bonus points for Carrot coming across as Clark Kent-like. Doesn't need to be Superman, but Clark Kent-like. Exra, extra bonus points for introducing New Reporter Clark Kent who does have an embarrassing affliction of levitating in his sleep and who boards with Mrs. Cake.