I do not care exactly where people are placed in their cockpit, as long as they have a realistic position (that they have blind spots and need to use mirrors). However, I would not want anybody using a non-cockpit view, because that is a different way of racing. But there is no point explaining this in more detail, as there is noone (atm) who is asking for that. And Kennett has answerd his own question, we only allow cockpit view because that is the only way to disallow the arcade-views.
As for the advantage of using 3 screens, it depends what you mean by advantage. It does not make you quicker, that is for sure. The biggest difference is that you are safer on track, because you see the cars comming up your side at an earlier point. In addition it is more fun with 3 screens.
I think the "advantage" one can get from investing in different equipment is perfect. This is our hobby, and there are many things we can spend money on to make the experience better (more powerful pc, better racing wheel, better pedals, more/larger screen(s), racing seat,trackIR, telemetry screen and other cool stuff). All these are small improvements one can make to have a more exciting and enjoyable racing experience without making you faster or more competitive (which could be unfair).
EDIT: Just in case it isn't clear, I would have no problem with the view Kennett proposed, but unfortunatley it is cockpit view on or off, that's all I can chose from.