So I was just thinking about those posts you get in the Discworld tag about the way belief works on the Disc and how Vetinari and/or Vimes is so integral to the way Ankh-Morpork works that they might just sort of… not ever die.
You know, the ones like ‘Vimes is going to become a god of policemen and he’s going to hate it”.
Well. What if it happens to both of them? There are two parts to the city, after all. ‘Proud Ankh’ needs taking down a peg or two (or seven) by Sam Vimes, and if anyone can terrify ‘pestilent Morpork’ into being better then it’s Havelock Vetinari. And they can drive each other mad with stealth puns for centuries, if they want.
Also, this would potentially make them literally Law And Order, and that just seems very fitting in a way that would probably annoy them both.