But I do know the first thing I'd do is attach El Paso to New Mexico. I'll post some of the other things later.
Going off of that idea...move the following counties to Texas: Otero/Lincoln/Chaves/Eddy/Lea/DeBaca/Roosevelt/Curry/ Quay/Harding/Union...they're basically Far West Texas anyway. Or, take those counties and add them to the Texas and Oklahoma Panhandles to create one new state. Put the rest of NM, including El Paso, in Arizona. NM actually wanted to be one state with Arizona, but Arizona voted it down...