Quite striking. Very classic and elegant. Wearing the ascot outside the shirt collar seems a bit louche (at least by contemporary standards), but maybe I should give it a try!
Two sleeve buttons is quite an old style, as near as I can tell. Nowadays we put on three or four, but I recently dug out an old photo of Anthony Nicholls (old Brit actor) wearing a full double breasted blazer, massive buttons, etc, but with only two widely spaced buttons on the sleeves.