DonDiego opines the list is somewhat lacking in villainous characters from the earlier days of television. DonDiego and television grew up together.
Fr'instance:

Mr. Phineas T. Bluster was a quite unpleasant early villain residing in Doodyville.

And Froggy the Gremlin caused mayhem in black and white whenever he plunked his magic twanger.
Oh, . . . here's the rest of the list:
20. Ben Chang from Community
21. The Cigarette Smoking Man from The X-Files
22. Wile E. Coyote from The Bugs Bunny/Road Runner Show
23. The Daleks from Doctor Who
24. Louie De Palma from Taxi
25. Russell Edginton from True Blood
26. The Evil Queen/Regina from Once Upon a Time
27. Teresa Giudice from The Real Housewives of New Jersey
28. The Governor from The Walking Dead
29. Roman Grant from Big Love
30. Victoria Grayson from Revenge
31. Richard Hatch from Survivor
32. Boss Hogg from The Dukes of Hazzard
33. The Joker from Batman
34. Erica Kane from All My Children
35. Klaus from The Vampire Diaries
36. Constance Langdon from American Horror Story
37. Lucifer from Supernatural
38. Lex Luthor from Smallville
39. The Miniature Killer from CSI
40. Clay Morrow from Sons of Anarchy
41. Abu Nazir from Homeland
42. Newman from Seinfeld
43. Number Two from The Prisoner
44. Mrs. O'Brien from Downton Abbey
45. Omarosa from The Apprentice
46. Plankton from Spongebob SquarePants
47. Spencer Pratt from The Hills
48. Puck from The Real World: San Francisco
49. Gordon Ramsay from Hell's Kitchen
50. Red John from The Mentalist
51. Syp Rosetti from Boardwalk Empire
52. Vern Schillinger from Oz
53. Arvin Sloane from Alias
54. The Smoke Monster from Lost
55. Alan Spaulding from Guiding Light
56. Sylar from Heroes
57. Sue Sylvester from Glee
58. The Trinity Killer from Dexter
59. Mona Vanderwaal from Pretty Little Liars
60. Amanda Woodward from Melrose Place