At this stage the scene was highly unstable; 3ds Max was ready to crash in response to any careless action, which is why the ground material was primitive - I placed the final texture in the Diffuse slot and finished with it. For displace I used a copy to have the opportunity to control the height and direction od the displace, without any changes in Diffuse (Fig.16).
I wanted the lighting in the scene to be mild, with degraded shadows - typical for cloudy summer's day. The light needed to be directed to delineate the model's form and to add some depth to it by contrast of highlighted and shadowed parts. For these goals, HDRI with a Dome Light were enough for me. Tests with HDRI met all the requirements mentioned, so I kept going with it.
I adjusted the Dome as a direct light (i.e. I didn't turn "store with irr.map" on). In this mode, Dome with HDRI gave more correct and detailed lighting than just an HDRI set as a texture for the Environment (Fig.17a).
I also tried turning on "store with irr.map" - all highlights in the scene were practically washed out, and to keep shadow details I had to twist out the Irradiance Map adjustments, which made render times longer and gave me even worse results.
As this scene was of an exterior type and had few places which were unseen and unreachable by primary lighting, the influence of secondary lighting was insignificant, so it was needless to adjust its settings whilst getting a realistic and pleasant look in a lesser time. Nevertheless, I turned "store with irr.map" on in the Dome's settings for night renders, but only because as a direct light there were planes that I used to imitate flashlights (Fig.17b).
Some more planes were placed inside the headlights. I turned off caustic in the global lighting settings to decrease render times, which is why the glass material with a Glossy effect let the light through badly, and the headlights gave almost no reflection to nearby surfaces. For night renders I decided to accentuate this effect, and for this purpose I placed more invisible planes at the outer side of headlights (Fig.18a - d).