I placed a GI light dome in front of the Original scene, turned the Quality up to 100% in the HDRI, finally changed the color of the shperes to a soft fuzzy mat. I wanted to see what render time looked like with a major light source added. The Radials are set at 25, with shadow(gray) (not soft)

Next I wanted to try a Zenith light Rig.

Then something with more reflection.

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Ockham's razor- It's that simple