I agree that Calendar Events need to be report suite specific and in some cases specific to a report as well.

I would also recommend that for certain reports like the Site Content >> Site Sections Report that when this report's metrics are set to Visits or Unique Visitors that the total is removed since totalling Visits or Visitors is not accurate. Any Visitors who visit multiple Site Sections will count as a Unique Visitor in each, but only count once in the total. An in-product explanation could possibly be used and replace the Total display.

I agree as well that the "None" should be a configurable setting but I recommend this setting be implemented as an admin setting in the admin console that an administrator would turn off "None" across the entire report suite rather than report by report. Also, when "None" is configured to not display, it's respective metrics should also be removed from being totaled as revenue and orders due now for example in the Search Keywords - Natural, Search Keywords - Paid and the Customer Conversion repo...

I agree entirely that Unique Visitors and Visits should be a default metric for all reports.