I love the Big 5 parks as they call them but I am not much into crowds. We try to always camp in dispersed campsites and stay away from any place that requires a reservation. Escalante/Grand Staircase fits this perfectly. You can start at Page and work your way up to Halls crossing and take the ferry (look at times because it’s seasonal). Work your way up to one of the greatest roads out here, the Moki Dugway and then up to Natural Bridges. It’s a bit touristy but you can get some great views and hikes. Go up towards Escalante and work down towards Calf Creek Falls for another great hike. Skip the campground close by the trail head and find a dispersed site off Hole In The Rock Road.
two fun slot canyon hikes are Peak A Boo and Spookey. Not too tough but fun.
PM me if you need a more detailed itinerary.