Suggestions by @christopher00h

Ivan Dixon

as The Constable in Lemony Snicket's A Series of Unfortunate Events (1984)

Score: +2

Orlando Brown

as Baby Seymour in Happy Feet (1996)

Score: +2

Ron Clements

as Producer in The Great Mouse Detective (1996)

Score: +1

John Musker

as Director in The Great Mouse Detective (1996)

Score: +1

Céline Dion

as Where are you Christmas in How The Grinch Stole Christmas (1990)

Score: +1

Matthew Broderick

as Peter Pan in Peter Pan (1993)

Score: +2

Alan Menken

as Composer in The Great Mouse Detective (1996)

Score: +1

Alfred Molina

as Dr. Watson in The Great Mouse Detective (1996)

Score: +1

Kenny Loggins

as (Some Other World Singer) in FernGully: The Last Rainforest (1980's)

Score: +1

You Need to Be Loved-Jermaine Jackson

as Best 70s Song in Best And Worst Of Music

Score: +2

Come Sail Away

as Best 70s Song in Best And Worst Of Music

Score: +2

Fantasy (Earth, Wind & Fire song)

as Best 70s Song in Best And Worst Of Music

Score: +2

Pierce Brosnan

as Sherlock Holmes in The Great Mouse Detective (1996)

Score: +2

Danny Elfman

as Composer in How The Grinch Stole Christmas (1990)

Score: +2

Tim Burton

as Director in How The Grinch Stole Christmas (1990)

Score: +1

Keke Palmer

as Young Sofia in The Color Purple (2005)

Score: +2

Chris Rock

as The voice of Black Trooper in Spaceballs (CGI) (2004)

Score: +2

Elmer Bernstein

as Composer in Spaceballs (1982)

Score: +2

Violet McGraw

as Suzy Johnson in Phineas and Ferb (2017-present)

Score: +4