I think it would be nice to keep the readme as low-level as possible. However, this is hard since we don't yet have a developer specific documentation where we can go deeper on a subject if we need to.

Easy to read sentences, and a natural flow between sections.

I suggest the root readme tells the consumer about the different packages, how they can use them - but no in-depth implementation documentation. We can do a drill-down inside of the package readmes, but we need to make sure we clearly link to them from the root readme.