Since LeBron is not married, the smart thing to do would be to leave some rooms unfinished so his future wife can put her stamp on the place. Otherwise, that bowling alley is likely to get the heave ho, in favor of a yoga studio.
BTW, a couple of years ago on the local parade of homes, I toured a house that had a detached 2-story gym building in the backyard that included a regulation indoor basketball court with a wood floor and a sports-themed home theater looking down onto the court. The driveway at this place was so long and steep that they had golf carts to ferry visitors between the house and the gym. I should have bought that house.