Best training docs for user training?

Hi all,

I'm a Power BI admin and am looking to put together Power BI Desktop training docs for my users. I'd like for this to consist mostly of public documents, as that's most efficient.

For lots of Power BI features, I believe that the official Microsoft docs are really good. But there are certain areas, like DAX, where the documentation is lacking.

What documents/resources(including videos) do you recommend for user training? What do you feel is lacking in Microsoft's documentation? Anything would help.