Next day (May-21), after a drive or horseback ride of the park, we値l leave towards Hanksville, taking the 163/261 and 95 as suggested by Kinless. We値l surely enter Natural Bridges NM.
Next day (May-22) we値l go from Hanksville to Kanab, driving through the routes 24/12 and 89, surely entering Bryce Canyon NP.
Next day (May-23) we値l go to the North Rim and make a short trip on horseback or hiking. That same day we値l return to Kanab, and perhaps continue the trip to Las Vegas.
What do you think? I know it's a lot for just a few days, but who knows if I ever return here, right!?