I am severely handicapped and can only play "Sitting" mode games. Unfortunately though, some games that are rated as "Sitting" actually require movements that are impossible for me, such as reaching down to the floor or physically swivelling around to face behind me.
I can move my upper body freely, but I cannot bend down or swivel around. There are lots of great games that work very well for someone in my situation, but there are also some that don't -- and unfortunately there's no way to know until after you buy it.
I realise I probably represent only a small number of Oculus Rift users, but I feel sure that I'm not the only one in this situation. The Rift gives me a sense of freedom that I can't experience in my real life and the addition of some type of "Handicap-friendly" Player Mode would free me up to take a chance on some of the more expensive games that I'm currently wary of (since I can't be sure if I'll actually be able to play them).