That's a great loop - we were bagged for the road section back too:)
The problem with road riding on Kauai is that other than that climb there aren't many other safe options for riding. Too much traffic on narrow roads... Maui is better for safe options (and consequently it is also easier to find a decent road bike for rent on Maui).
I get it but the sad thing is that the roads aren’t any more narrow than what I rode in France for 3+ years. It’s the drivers of big cars who wouldn’t be used to gaggles of riders checking out the island on two wheels.