I think we should focus on improvements that *really* make a change.
I've been missing from time to time the ability to sort my messages on *type* rather than file or line together with an IDE that present these in a tree (GUI) view where each warning message type node can be expanded or compressed. At least for big projects written in C/C++ where people have accidentally turned off important warning messages and then some other guy have found out that we need to turn it on (again) this would be a useful feature. This mainly because it's easier to fix a set of similar warnings at the same time as the solutions often are more closely related than warnings of different kind related solely by line locality.
Now, of course, D isn't C/C++ and D programs don't generated as my garbage output as C/C++ does when compiled...but still could become handy in very large D projects.
