Completely agree on this, wrote it before :- )
Typical Sketchup user doesn't have patience for Vray, nor performance for Maxwell (or some more obscure older pathtracers that still linger as legacy). Corona, plus perhaps cheaper, special licence for Sketchup would be great business step,
if marketed properly. It could be integrated almost as one button into its simple UI. Ten of thousands of users would be beyond the scope smaller DCC apps could ever bring on.