The Canyonlands aren't as famous as Arches, but the park is definitely worth a visit. It's one of my favourite parks of our journey. The irony is that we saw the most beautiful arch here, the Mesa Arch. It was a very short, easy walk towards it and yes, if you're there, go see it.
We visited more view points throughout the park and did another short hike to Upheavel Dome. However, what stays with me the most is the Grand View Point. It is one of the most beautiful landscapes I have seen in those three weeks and I recommend you to stay for the sunset. It is breathtaking.