Wichita Falls is an affordable, mid-size city with a friendly downtown arts/food scene, university events, easy parks access and Lake Arrowhead for boating and hiking, plus the large Sheppard Air Force Base nearby—comfortable for multi-week stays and weekend exploration.
If you want a change of pace, Lawton, Oklahoma (about 50–55 miles north) offers extra dining, museums and access to the Wichita Mountains for hiking and short overnight trips.