A medium city with a agradable temperature and amazing peoples. The Park of the Nações Indígenas is a local to go to run and apreciate the nature.
I live here. I know that makes me bias. But Campo Grande is not a "very dangerous city". It's the capital of the state but has this small town feel to it. There are not a lot of tourist attractions here, one day is enough if yu want to just see the sites. Most people only pass by on their way to Bonito and the Pantanal. If you have some time i recommend a walk at Parque das Nações Indígenas, where there are also two good museums to visit. Or maybe a drink at Mercearia Bar downtown.
Very dangerous city. This is good place to take a tour to Pantanal - biggest wet lands on the planet. Order a trip before you come, arrive early in the morning and ask to pick you directly from the airport to the tour. When you come back you will have to spend one night in hostel or fly in the evening.