One of the most problematic features of Discover or "Ad-Hoc Analysis" is that every single change you make has to refresh the whole data set. What would make life so much easier is to have an "Auto Refresh" checkbox whereby if it's unchecked you can add metrics, segments, change date ranges etc but until you hit refresh nothing will happen. Sometimes it takes me an age to make all the changes I need because it has to refresh every time, if I could make a group of changes and then refresh it would speed up what I'm able to do significantly.
