Dallas has no state income tax, which is a big plus. Atlanta's property taxes can be lower depending on the specific county, but you'll pay state income tax. Both have awful traffic, but Atlanta's public transportation is arguably slightly better, although still not great. The music scene in Atlanta is definitely more vibrant and diverse. Dallas is more corporate, while Atlanta has a more artsy, creative vibe. If you want cheaper housing overall, look to the Dallas suburbs, but Atlanta's cost of living is a bit lower in the city core.