I believe it would be a cool idea if for the next firmware update to add a feature that enables a person to scroll through the pictures and add one of their pictures as a background for the menus and playing screen.
My experience with another player that does this is that the menu screens are already pretty busy, and putting a picture behind that just makes it a big mess.
I think Ideas like this are cool but unnecessary, and could rob power and performance. Perhaps to make this possible a version A and Version B could be done with the firmwire. One Supports pics as back ground the other does not. You choose.