OK, I personally have always viewed Arthur as a bit older than the rest of the league. That is why I'm choosing an older actors and actresses for the respective roles. I also feel older more established actors would somehow bring more respectability to the role than seeeing some current "it" boy heartthrob in the role
Also, Aquaman has a stigma associated with him that he's "lame" so i don't see A list directors and actors signing up for this. With the right script though it can propel the stars to A list status.
Director: John Stockwell, he's a decent director, but what he has over many other film makers for this particular job, is his beautiful underwater cinematography as evidenced by Blue Crush and Into the Blue
UPDATED
Stars:
Orin/Aquaman-David Wenham
Queen Mera-Kate Walsh
Orm The Ocean Master-Oded Fehr
Story: In my idea, Orin will have already been king for some time, and a father. It would start on his son Arthur's first birthday, and Orm having always resented his brother for being half human and having the love of Mera finding an ancient book of the wizard Atlaan's and a prophecy about a blond king who'll bring about the destruction of Atlantis, and doing what he can to destroy Orin and take his place on the throne which he feels is rightfully his. In the book he finds where to get ancient mystical Atlantean armor and that's where his suit comes from. he'd have some help from Atlanteans he's recruited to his cause, and the young Arthur would go missing. His son being missing would cause conflict between Mera and Orin, and while his son is missing we'd see him go from clean cut happy King, to his beard starting to grow, hair getting longer etc. He'd look more and more barbarian like the longer his son was missing. Eventually, he'd find out what happened and a MASSIVE underwater battle would break between the two factions of Atlantis, those on Orm's side and Orin's followers. the battle would culminate in an epic showdown between Orm and Orin. The battle would be intense, with Orm's mystical armor and trident, and Orin commanding creatures of the sea, some of which we've never even seen before. In the end, Orin would be victorious, but the battle would cost him his hand. in the end he'd get his son back, and we'd see him fitted with the hook hand.
I'd have the entire movie underwater. He'd surface in the second which would revolve around Black Manta. there'd also be some dialogue between Orm and Orin about him enjoying his time with the surface scum so we'd know he's already known above as Aquaman