Basil Rathbone will always be Sherlock Holmes to me to matter what other great adaptions come down the pike. He, to me, is perfect. He is also very much like I imagined Holmes in the books - not to mention infinitely handsome! He is MY Mr. Holmes!
A very pretty drawing of good old Basil -- I knew at once it had be be him, you've represented his characteristic features very well, I especially like how you drew the lower part of his face. And for some reason I have to stare at his ears the whole time, you did this edgy shape of them so gracefully.
I'd say though the shading needs overall some little improvement, more.... details? Well, I can imagine your reference pictures are not of best quality, old as they are. But I'd try to smuggle some finer details into the drawin' nevertheless.
And talking about the model.. yes, yes, handsome gentleman INDEEEEED he was, our dear Mr Rathbone.. I always admired and feasted my eyes on that sort of aristocracy that he radiated -- he has this kind of face I want in my imaginative 'private museum of pretty things and people' (short PRIMOPTAP) chiseled out of marble. :'D