My house in California had a black bottom granite pool. The black bottom was nice early or late in the year, because it self heats. I was actually swimming from Easter to Thanksgiving. However, in the middle of the summer it wasn't as nice, because the water was then too hot to be refreshing. In the winter I kept the cover off to heat the pool, but yet I wanted the cover on to keep the debres out. In the summer I wanted to keep the cover on to keep the water cool, but it's a pain to put on and take off each time you want to use it, making you not want to use it as often - unless you have a mechanical cover, which I did not. The warmer water also uses more chemicals. More acid because algae loves warm water. More chlorine because hotter water causes the chlorine to evaporate faster. I also had to clean my filter more often than if it wasn't a black bottom. Not really an issue, it takes 15 minutes and a garden hose, but none the less....
Deeper pools also had a higher home insurance premium. As did diving boards and slides. My pool was 3' to 8' and about the same size as you are looking for. I added a 'landscaping rock' near the pool which I used as a diving rock. Insurance company didn't care about it, as it wasn't a diving board. They also wanted a chain link fence around the pool, which I had no children, so I wasn't going to uglify my yard for it. I had a completely fenced yard with locking gate that they, tongue in cheek, called good enough.
Do over? I think I would have a black bottom again. I love to swim, so the ability to swim sooner and later in the year was very nice. Not to mention the possibilty of the water freezing and ruining the pool was a non issue.
EDIT: Dollar wise it was over $45k, because it wasn't just a pool. I also had landscaping rocks, soaking tub and waterfall, as well as the landscaping to make 'it work' and tie it all in to the deck and gazebo.
