A great thing about just using sqlite as the format is that you get lots of potential features. Sure most applications don't need full SQL power just to save an

A great thing about just using sqlite as the format is that you get lots of potential features. Sure most applications don't need full SQL power just to save and load data. But then at some point you might want more advanced functionality, or migrate to a new structure. And both you and your users get tools for free, e.g. to extract data or fix problems, or just look around. Other applications can quite easily read your files, without you needing to write various language libraries. Very few projects get around to building that kind of tools for their made up format. I could agree about the single implementation, but if the alternative is making something new up I am not sure in what way that would be better.