Good point EyesOnly.
I fear Brandon Routh was hunted and cast due to his canny look and style which was very comparable to the late, great Christopher Reeve and would really click with audiences, which I think he did but only for that reason.
Cavill will face a great test here, a real departure from everything Christopher Reeve's legacy gave up and trying to create a new take on Superman on his own shoulders without depending on homages Reeve's style or voice even.
But as you say I too am convinced he's doing it right, and will be a wonderful actor as Superman and Clark Kent we see on screen. Can't wait for his return!