Great choices. I would add the Mantle brothers in Dead Ringers; Horace and Dr. Meirschultz in the 1934 camp classic Maniac; Dr. Jonas in Conspiracy Theory--based on a the career of a real doctor, Ewen Cameron--the subject of two documentaries "The Sleep Room" and "Eminent Monsters."

You probably know this, but at select theatrical showings of The Tingler, seats were wired to administer a slight electric shock, which explains the prologue warning (and which would make William Castle a bit of a mad scientist himself).