I once had an idea for a Hamelin themed McDonalds crew. Where the rat catchers were employees, the obedient wretch was the kids mom, Hamburgler was a convict gunslinger, not sure about the rat kings.
You could probably also use a mercenary convict gunslinger for Hamburgler, or anyone else with a gun such as the forgotten marshal, or guild autopsy. If you go guild Mcmorning you could use guild guard/sergent as officer Big Mac, the government proxy as Mayor McCheese and the captain, as the captain. You can use a canine remains as Ronald's dog Sundae. (Not sure if you know that, look up "the wacky adventures of Ronald McDonald" there's lots of obscure characters in there such as the McNuggets.) Also Shikome could make for an alternate Birdy.
That's all I can think of for now.
Oh and a Guild Autopsy as Officer Big Mac.