DiCaprio as the young TR (viciously lampooned as an Eastern 'dude' when he first showed up out west) might actually turn out better than expected, since that period of his life was all about the transformation of his image.
He entered the New York state assembly in 1881 at age twenty-three, having overcome poor health just like his idol Abraham Lincoln. He still appeared unmanly, and newspapers and his fellow assemblymen ridiculed his "squeaky" voice and dandified clothing, referring to him as "Jane-Dandy," "Punkin-Lily," and "our own Oscar Wilde." The New York World proclaimed him "chief of the dudes." Duly insulted, he began to construct a new physical image around appropriately virile Western decorations and settings, foregrounding the bodily attributes of a robust outdoorsman that were becoming new features in the nation's political iconography.
http://www.press.uchicago.edu/Misc/Chicago/876071.html
He entered the New York state assembly in 1881 at age twenty-three, having overcome poor health just like his idol Abraham Lincoln. He still appeared unmanly, and newspapers and his fellow assemblymen ridiculed his "squeaky" voice and dandified clothing, referring to him as "Jane-Dandy," "Punkin-Lily," and "our own Oscar Wilde." The New York World proclaimed him "chief of the dudes." Duly insulted, he began to construct a new physical image around appropriately virile Western decorations and settings, foregrounding the bodily attributes of a robust outdoorsman that were becoming new features in the nation's political iconography.
http://www.press.uchicago.edu/Misc/Chicago/876071.html