Last year, he was nominated to play Finarfin. I think he deserves a chance this year. He has done a great portrait of the slightly fanatical Norwegian explorer Thor Heyerdahl in the Movie Kon-Tiki. He has a charisma that says he has a good heart but also expresses devotion and perhaps relentlessness. I believe he would do a wonderful job with this role. He is, as Turgon should be, very tall. As a bonus, he looks a bit like Tom Hiddleston (Fingolfin, who of course is Turgon’s father)
I've been imagining Joseph Gordon Levitt in this role. He's a versatile actor with a very expressive face, which seems important because a lot of his role will be reacting to things--once Gondolin is set up, he'll mostly be in one place and responding to people and events as they come, and even in this season he's notable for how he responds to their abandonment on the ice. I can see him being stern and even forbidding as a king, but also loving and affectionate to his family. I think he'd do very well as a grieving widower and newly single father in this season. And I think he has a good look for a Noldo prince.
(Sooo...I know height is going to be a sticking point, but here's my defense. First, Turgon is a pretty central character and his actor's going to have to carry a lot of emotional weight over a long stretch of time, so I think this is a situation where acting ability and characteristics are more important than a physical trait that doesn't have much to do with the plot, especially since Turgon is less about physical heroics than a lot of other characters. Second, some creative camera work could make him appear taller. One approach that I think could actually work really well for the character would be to include relatively few shots where he's right next to other people. If we mostly see him alone in the frame or at least somewhat apart from others, that creates a sense of isolation and loneliness that I think would work very well for the bereaved king of a hidden city. It would also heighten the impact of scenes where he's physically close with others, like, say, little Idril. ... Okay, there's my case. 🙂 I gave it my best shot!)