A first person mode on VR would be great, except you need to look at the personal aspect of it. We have experimented using the Ochulus rift doing a walkround of a building we designed a BIMX walkthrough on. The problem we were having was people were feeling dizzy or sick after wearing it for more than 5 minutes and also were struggling with the concept of looking at things to move forward as they kept wanting to walk in Real life. Granted these days you can get (at a large cost) these roller pads to enable you to walk but stay in the same position and the walking tanslates to movement in the game, however it will be a long time before that technology would be down to the price a standard gamer can afford. To us we have it availiable as a gimmick but find when doing public presentations at planning meetings people find navigating the building on a tv using an x-box controller is much more comfortable. Basically you would need to develop something that would appeal to the masses and not have any bad effects to be able to allow for the coding and facilities to be VR for any new game.