You know, I still don't get why they needed to make him up as much as they did for "The Menagerie". Sean Kenney was chosen because he apparently had superficial similarities to Hunter -- but to my eye, they're actually even closer than that.
As a young kid watching The Menagerie, I always wondered why wheelchair-Pike had different colored hair than normal-Pike. It looked like Pike decided to bleach his hair but I chalked it up to the radiation damage.
For some reason, when I was a youngster, hair color was a large part of the character's identity, in my mind. For example, in "Alias Smith and Jones" when Roger Davis replaced Pete Duel after Duel's suicide, I remember thinking..."that can't be the same Hannibal Heyes, he has different colored hair!"