In the last couple of months, I've seen about half a dozen requests for the 'cancel' button to be returned (yes, the same Cancel button that almost no one was using when it was present). These requests are usually from new editors.
The toolbar is cluttered, and redesigning it (e.g., so that it can be zoomed in without eating half the screen) is probably not going to result in such dramatic space saving that this almost-unused button would be worthwhile. However, what about an escape clause under the Help menu, or next to the "Switch to source" item in the Page options menu?