. . . I still feel that the grip should be higher but there's not more that can be done.
You know I'm a fan of getting the grip as high as possible, but you're right that there isn't too much more that can easily be done. I will say though, that the greater angle of the Hogue really forces your hand up close to the bottom of the stock. The Riffe, at least for me, tends to direct my grip at least an inch lower.
Not the best pics, but you get some sense of the difference