I was there a few weeks ago - rode Rabbit Ears over and back tough and beautiful ride - tho once you are headed to Kremling the shoulder becomes quite narrow and the drivers/trucks nowhere near as accomodating as the Steamboat side. Another ride is up to Steamboat Lake - beautiful. DONT take the Mosquito Pass loop - construction is a nightmare. There is a very nice loop if you head out towards Craig and double back on ?mile road. Shoulder on 40 not so great tho towards Craig.
I did Rabbit Ears, very nice. The grade was around 7% for most of the ride and that view of the valley is spectacular. As Crockett said, the shoulder narrows in parts. Nice ride though. I'll do Steamboat lake next time. thanks!