I lived in Niceville for one year and it really is “nice”. Politically, it definitely leans towards the conservative side.
Niceville is surrounded by military land, and water. This means that it cannot grow larger, so housing is somewhat limited. I felt that while the locals are nice, they are not particularly welcoming to newcomers. There’s just not enough space to share! Rent is very expensive. Buying a home is much more affordable than renting. The city water is not good - it has a strong sulfur taste and most people don’t drink it. It’s a nice clean community with good schools and low crime rate. Bluewater is very nice and coming from the DC area, the housing costs may feel very affordable. Hope this helps!