Would it be useful to enable adding and ordering of columns in the Grids section of the Properties pane?

 

The vertical position of the field names in the Grids section would correspond to the left-right position of the columns in the grid.  Alt+up/down keys could be used to quickly change this ordering.

 

An "Add Column" ... cell could be added in the list of columns for each grid.   Typing in this cell could activate a dropbown box containing the names of all fields, "filter as you type".  Once a field is entered in this box, the alt+up/down could be used to place the column in the desired location.