It seems to me that, while high resolution componentry can help better portray accurate RELATIVE height between instruments/performers (it does IME), the best (only?) way to accurately reproduce realistic height of vocalists while maintaining accurate relative height to instruments is to use speakers that are tall enough and designed to do so. Perhaps one reason for the new craze re: "tower speakers".
If you raise the height of a floor-standing speaker to increase the height of vocals to near-realistic proportion, don’t you also raise the perceived height of the lower-placed instruments above realistic perceived height if the RELATIVE height remains constant? Not to mention the changes in tonal balance that usually result from moving low-frequency drivers farther from the floor. Time- aligned speakers like Thiels (I know) and your Vandersteens (I would think) don’t take well to changes in relative height of the drivers to the listeners ears as their dispersion characteristics are part of the time-aligned design. Better room treatment to dispose of the overly-wrought midbass frequencies that mask detail and resolution will be a better solution IMO as will moving your Vandy's to a more near-field listening position away from the rear wall.
It is certainly possible to better optimize all of these attributes through experimentation by raising speakers with stands, but long term listening will likely reveal the compromises described above.
Dave