Easy-moderate hike with a little incline. Good for trail running. The scenery changes along the trail so it doesn't get boring. Views at the top are pretty. The one think I'd do different is also go to the lookout trail at the top. It is about a 0.6 mile trail that heads south off of the main tombs thumb trail and people said there were amazing views there.
Off the main trail there are several side trails, each with unique scenery. These detours were worth checking out.