I stand by my previous assertions: Eva Green for the Scarlet Witch, Aaron Eckhart for Captain America, and some talented unknown for Thor (not Brad Pitt, please God, anything but).
I vote Chiwetel Ejiofor for the Black Panther.
You have to admit, Ultimate universe Thor looks like Brad Pitt. He could bulk up Troy style, but I doubt he’d do it, so don’t worry, Kytheria. 
Ditto. I’ve liked Cheadle ever since Picket Fences, but he’s not the super-hero type.