Suggestions by @drdocter

Idris Elba

as Smaug in The Hobbit

Score: +4

Will Poulter

as Bilbo Baggins in The Hobbit

Score: +2

Stephen Root

as Oin in The Hobbit

Score: +2

Andrew Garfield

as Bard in The Hobbit

Score: +2

Paddy Considine

as The Master of Laketown in The Hobbit

Score: +2

Helena Bonham Carter

as Dis in The Hobbit

Score: +1

Javier Botet

as Gollum in The Hobbit

Score: +3

Mike Myers

as Great Goblin in The Hobbit

Score: +3

David Harbour

as Beorn in The Hobbit

Score: +3

Tony Revolori

as Alfrid in The Hobbit

Score: +1

Erin Kellyman

as Tauriel in The Hobbit

Score: +2

Benedict Cumberbatch

as Thranduil in The Hobbit

Score: +2

Ben Kingsley

as Balin in The Hobbit

Score: +1

Matt Smith

as Elrond in The Hobbit

Score: +2

Gustaf Skarsgård

as Nori in The Hobbit

Score: +2

Nathan Lane

as Dori in The Hobbit

Score: +1

Chris Hemsworth

as Kili in The Hobbit

Score: +1

Sam Heughan

as Fili in The Hobbit

Score: +1

Joel Edgerton

as Bifur in The Hobbit

Score: +1

Karl Urban

as Dwalin in The Hobbit

Score: +1