I think WiiFit had a good approach, and I enjoyed my time with it. The problem in the end, though, was that there were no rewards for your successes in the game (unless you consider better health a reward). Whatever Nintendo is doing with this initiative, I hope that there are designers on board that realize that you need to be able to unlock things, even if they're just little mini games or pieces of a puzzle or whatever. Gamers love to unlock stuff for all of their hard work.
Obviously I have no idea what QoL will end up being, but I know that one thing that Nintendo does best is to make games, and I hope that ultimately it is the core of whatever this device or platform or software ends up being.