Users should be able to navigate through the elements of RadPivotGrid using a keyboards. For example, moving between cells, collapsing headers with space, etc. 

 When there are a lot of items, it is quite difficult to find the ones you need in RadPivotFieldList. There could be some way to search within the properties.

If a group has only one item in it, I only want to show the total row and not being able to expand it.

As a user I would like QueryableDataProvider to avoid blocking the UI while executing the query on the database server.

As a user I want to hide the Grand Totals for specific groups.

See the attached image.

Steps to reproduce:
1. I checked the checkboxes 'Product' and 'Price'. The Product field added to row labels, and price to values.
2. Unchecked the 'Price', the price field removed from the pivot.
3. Unchecked the Product, doesn't  remove the products from the pivot.

Applying "% Difference From" total format to a calculated description formats the calculated data in RadPivotGrid as double, instead of as a percent.

Available with the R3 2016 SP1 release.

Users should be able to select individual or multiple cells of RadPivotGrid.

Available in the 2016 R3 Release.
Please take a look at our help article for more information: 
http://docs.telerik.com/devtools/wpf/controls/radpivotgrid/features/selection

Implement sorting by clicking on headers, like in RadGridView.
Unfortunately for Telerik, Infragistics have this feature:
http://help.infragistics.com/Help/Doc/WPF/2015.1/CLR4.0/html/xamPivotGrid_US_Sorting_Data.html

Currently the header of that column says "Grand Total" instead of the aggregate name.

It happens when you change the distinct values selection several times. The PivotGrid disappears after the exception is thrown.
I managed to reproduce it in the demo by repeating this action around ten times.

Available in LIB version 2016.2.606, it will be also available in the 2016 R2 SP1 release.