Tough one. Steve McQueen in the Great Escape jumping the barbed wire fence on the stolen motorcyle is hard to beat for ‘cool’.
Yeah - not sure if OP was trolling. Dirty Dozen and Great Escape are two of my all time favorites. Too bad Charles Bronson has passed away - he could give the definitive answer :) Steve McQueen certainly cultivated a cooler disposition (which probably answers OP’s question), but Lee Marvin was probably the better actor.
Time to dig out The Man Who Shot Liberty Valance and The Blob, two of my all time guilty pleasures . . .
Did his own motorcycle stunts.