I have chosen a route to produce content via the XML format that is used in the Tuscany Demo. This is rather than choosing one of the engines and the common object import format. The XML content is very rudimentary. It could be expanded to include animation, sound queues, Etc.
Honestly, I would not base a game around the Oculus World Tuscany demo. It's fine as a simple example, but you are going to spend a lot of time fixing it up to make a full game. Just use something that is already fully featured like Unity or Unreal.
I was kinda hoping someone here would see the opportunity in using the xml format as a platform for parametric world creation. Yes of course the engines with their complex editors and gui environments offer immediate productivity. But I want to go beyond the fbx formatted object placement and proprietory lock-in that occurs when you put objects in and manipulate them in these engines. I see a great duplication of gui data context hassle and editing environment maintenance that is probably 90 per cent of the effort behind these engines.
I'm looking to put animation in the xml format using the POV scene format (nodes etc) offered by the ImagTech boys (mobile graphics). I did a perl port of their format a few years back.