Being a Time Lord you can forgive Matt Smith for looking into the future-Yes his time as the Doctor maybe finite but he sees no reason why the role will hinder his career when he decides to vacate the TARDIS.
“I don’t think good actors get typecast. In ten years’ time I’ll be playing very different parts than I am playing now. So there is plenty of time for me to evolve as an actor.”
Matt’s not the only thing that’s evolving- the role of the Doctor (of which there’s nothing else like out there) has changed during Matt’s tenure:
“I can never relax because I’m always pushing myself to the highest level but it’s nice to enjoy the fact people have accepted me as The Doctor and enjoy the things I do.”
Its clear looking back to Matt’s first appearance in the TARDIS to the flaying arm conclusion of Night Terrors that Matt has changed; he’s managed to capture that wonderous glint and mischievous smile of the Doctor and the weariness of a near a thousand year-old man.
Long may he continue to evolve.