Joshua Tree in a Day - Advice of order
 

My family will be travelling through Joshua Tree National Park in early April and we will have one day. We will be arriving and leaving via the West Entrance.
We want to do some sightseeing at the main iconic sites and some light hiking. We will not be climbing. We plan to be in the park around 10:30 am.
This is what we are thinking but we would appreciate any thoughts.

1. Joshua Tree Visitor Centre

2. Cholla Cactus Garden

3. Arch Rock Trail

4. Skull Rock and Jumbo Rocks Campground

5. Lunch in Joshua Tree and check out little shops

6. Barker Dam loop trail

7. Hidden Valley Trail

8. Keys View for sunset

We'd also like to see the Wall Street Mill trail and possibly the Hall of Horrors but we're not sure where they fit into this tentative itinerary.

What we'd like most is a sensible order of the spots we want to visit that makes sense and any special nuggets that we have missed.
Thanks!

You do want to take in the ocatilla trees, so look out for those. There is an impressive patch off the main road. Also, check out an oasis. I don't have a map in front of me, but it's fairly easy to get to. Overall, realize what makes this place so special. It is the meeting of two different deserts, and you can detect the change from one to the other if you are paying attention.

Thank you for your ideas! Much appreciated :)