Excellent plan.
I would only make one change: Leaving Tusla head south to the Wichita Mountains near Lawton.
I find the area fascinating
https://www.fws.gov/refuge/wichita-mountains
I would then head west on Rte 62 to Rte 287 to Amarillo. I really have enjoyed that drive and would do it again.
Little longer day but worth it in my opinion.
Have fun!