I've visited Killeen several times. My SIL was stationed at Ft. Hood, and daughter teaches second grade right outside it in Killeen.
One of the strangest things I've noticed about Killeen, is that the whole town seems to be made of bricks, houses and all. SIL says it's good because you don't have to keep painting it!
When there in the summer, it was hot and windy, rained a lot but was told this was unusual, and was there this last March and raining most of the time. And my kids had no hesitation in driving over half the state to get to different book and craft stores, but others might want to stay closer to home, and there are many stores within easy driving distance there, because of the large amount of military families.
I would suggest that you arrange to visit both of these places, at different times of the year. And when there, do as I've told my kids to do, beg, borrow or buy a police band radio. Then listen to the police calls and write down the addresses or areas.
In my town, one of the prettiest to drive past has the worst reputation for constant police calls. And do go to the police department and ask them for suggestions.
Good luck on finding a new home.