For the FB Marketing connector, it seems to me that the docs would benefit from something to the effect of "The default tables from the Ads Insights table are very large and heavily throttled, so unless you currently have Advanced level API access, selecting only the fields you require with Custom Insights is probably the option for you", combined with a screenshot with a common example. I.e. this should be promoted as the primary option for everyone who wants to get started with the ads_insights table. The FB docs are so convoluted that it took me hours to figure out how to set up a basic report, and it appears that more people than me are running into this, given how often this question appears on these channels.