Suggestions by @jackamos2000

Jensen Ackles

as Hal Jordan in The Green Lantern

Score: -1

J.J. Abrams

as Director in Superman

Score: 0

Ian Somerhalder

as Lex Luthor in Superman

Score: -1

Logan Williams

as Barry Allen (Child) in The Flash

Score: +2

Michelle Harrison

as Nora Allen in The Flash

Score: +2

John Wesley Shipp

as Henry Allen in The Flash

Score: +2

Keiynan Lonsdale

as Wally West in The Flash

Score: +1

KJ Apa

as Wally West in The Flash

Score: +2

Grant Gustin

as Barry Allen in The Flash

Score: +1

Candice Patton

as Iris West in The Flash

Score: +3

Imogen Poots

as Iris West in The Flash

Score: +1

Jesse L. Martin

as Joe West in The Flash

Score: 0

Dennis Quaid

as Joe West in The Flash

Score: +1

Luke Pasqualino

as Cisco Ramon in The Flash

Score: +1

Carlos Valdes

as Cisco Ramon in The Flash

Score: +1

Natalie Dormer

as Caitlin Snow in The Flash

Score: +1

Danielle Panabaker

as Caitlin Snow in The Flash

Score: +2

Tom Cavanagh

as Harrison Wells in The Flash

Score: +2

Alex Pettyfer

as Eddie Thawne in The Flash

Score: +1

Rick Cosnett

as Eddie Thawne in The Flash

Score: +1