The Geometry 3D mode works exactly like 3D Vision, but in VR more 3D does not automatically mean better 3D. Your reference for comparisons should be the real world not some over the top monitor 3D effect, it’s called Virtual Reality after all. :)
Usually settings are dialed in so that 3D proportions look similar to what you experience in reality. You can get ‘more 3D’ by raising the Eye Separation, but that also means getting wrong 3D compared to the real world. And vorpX on purpose doesn’t allow really extrem values, because those make the world look strangely small and lead to an rather unsettling feeling for many people after a short time.
This is no error, not even a flaw, it’s just meant that way.
In Z-Buffer-Mode things are different. More 3D, especially in the forground would be a good thing here, but that is technically impossible in this mode.