power bi sources
Keep Excel on the desktop on par with the data sources Power BI has access to. Just a few of the examples that the August 2017 build of Power BI has that aren't even in Excel 2016 Fast Ring build yet:
There are many more, but you get the idea.
Mimoune Djouallah commented
we are using BigQuery to feed some PowerBI reports, and we love to have access using PowerQuery in Excel