AT:Sonamy Joker and Harley Quinn

Here's who I think which Sonic character would be which Batman character:
Dr Eggman - Bruce Wayne/Batman 
Scratch - Robin/Dick Grayson
Grounder - Another Robin, just cuz.
Sonic - Joker (obvs)
Tails - The Riddler
Knuckles - Bane (obvs)
Amy Rose - Harley Quinn (obvs)
Cream - either The Ventriloquist or Baby Doll, with Cheese being Scarface or Button Eye 
Shadow - Two-Face 
Rouge - Man-Bat (thought she would be Catwoman, too bad)
E-123 Omega - Mr Freeze 
Silver - Blight 
Blaze - Firefly  (obvs)
Vector - Killer Croc (obvs)
Espio - Maybe Scarecrow?
Charmy - Maybe Killer Moth?
Tikal - Phantasm
Mighty -Doctor Death (bit of a oddball)
Big - Clayface
Vanilla - Catwoman  (I can just imagine Vanilla flirting with Eggman)

Those are the ones from the top of my head. Who would you cast?