I'd like to see the elimination of modal pop-up dialogs whenever possible, perhaps favoring status bar notices and logging instead - specifically in the case of I/O errors but there might be others.
For example: "I/O Error - The following I/O operation could not be completed: C:\Program Files\jEdit\#Untitled-1#: Cannot save: java.io.FileNotFoundException: C:\Program Files\jEdit\#Untitled-1# (Access is denied)". This is information that is nice to have, but not something I want to see every 30 seconds until I get around to either A) saving the file in a location I have permission to, or B) turning off the default global autosave setting. Note that I do understand why this particular message appears, and that there are several ways to remedy it - I'm just suggesting that when this *does* occur, a modal dialog isn't the way to handle it.
Another one I see a lot is "The following nn I/O operations could not be completed:" followed by a bunch of character encoding warnings when I do a HyperSearch on a subdirectory tree that has some binary files mixed in. Again this might nice-to-have info, but not something I want to be bothered with whenever I am too lazy to narrow the HyperSearch Filter down from "*" (which is nearly always).
If I am manually saving a file and an I/O error occurs, that is when I would want and expect a dialog to pop up.