My biggest suggestion over anything else is mastering the consistency of immersion with proper angles and distances when doing mutliple positions but primarily laying and seated CG since these are the two positions most viewers are in when watching VR.
SomeJAV has really seemed to nail this and I wonder what cues or training they use to keep it so consistent.
SLRO examples of this is Neural Link with Mellisa Stratton both in seated and laying CG, EuroTrip step sisters with Kama Oxi in seated cowgirl (this is perfect distance and angle where we feel as if you are right there with Kama as you gaze into her eyes), and Stress relief with Venus Vixen.
My suggestion would be:
Study the angles and distances and have the girls practice the perfect distance and angle on a 'dry run' for both seated and laying CG. Then maybe have a 'quality assurance guy' watching in realtime and directing whether she is in optimal position or not by a green light (perfect viewing angle/distance), yellow light (coming slightly out of optimal range), or red light (out of optimal viewing range). The light would be above and behind the male or even better a small light in between the dual cameras of the rig so the girl would never lose eye contact.
I think this is potentially a not too complex way of making the process easily repeatable and consistent.
Consistently being able to gaze into the eyes of the girl you are fucking while also being able to see her simultaneously going up and down on your cock takes VR immersion up a whole nother level.