I offer a philosophical aside for your consideration.

I wonder what concept of ‘realism’ you are using and what values it embodies. A more ‘realistic’ VR—if that means simulating, evermore faithfully, the realities we already create through the senses, cognitive apparatus, memory and imagination—may be a misguided ambition. Throwing a veil of illusions too easily confused with the reality evolution has already fitted to our survival needs may not be a good idea. ‘Perceptual enhancement’ may be a better ambition for VR which has the potential to enhance fitness for survival by transforming and expanding realities.

Anna Soska

Realism is a complex concept. Some research shows that if people have visual feedback from their bodies on space, they respond more appropriately to the movements. So having some feedback from where their arms and foot are on space might help. The delay between movement and visual feedback has to be diminished as possible. Some of the old HMD, such as DK1, had a really low frame rate creating a delay that increased motion sickness. The objects presentation is also important. It is necessary to have a certain number of 3D objects to help with depth perception and motion parallax. Also, there is a fine line in realism of VR environments that if crossed could get you into the uncanny valley. So you might not want to try being too realistic. There are so many factors... the first step might be to understand how realistic you want to go for, and if the realism would be beneficial to the task you want to achieve.