Suggestions by @bradleysigma

Anna Kendrick

as Sarissa in The Dresden Files

Score: +17

Iwan Rheon

as Lloyd Slate in The Dresden Files

Score: +5

Benedict Cumberbatch

as John Marcone in The Dresden Files

Score: -23

Robin Wright

as The Leanansidhe in The Dresden Files

Score: -18

Kristin Chenoweth

as Aurora in The Dresden Files

Score: -9

Rory McCann

as The Erlking in The Dresden Files

Score: +15

Ian McShane

as Donar Vadderung in The Dresden Files

Score: +19

Tilda Swinton

as Mab in The Dresden Files

Score: -11

Terry Crews

as Hendricks in The Dresden Files

Score: -11

Aubrey Plaza

as Maeve in The Dresden Files

Score: -8

Diana Rigg

as Mother Summer in The Dresden Files

Score: -2

Maggie Smith

as Mother Winter in The Dresden Files

Score: +12

Andy Samberg

as Waldo Butters in The Dresden Files

Score: -8

Alan Tudyk

as Bob the Skull in The Dresden Files

Score: +31

Brian Blessed

as Ebenezar McCoy in The Dresden Files

Score: -14

Martin Starr

as Harry Dresden in The Dresden Files

Score: -40