I know it seems like a productivity improvement, but switching from eraser to brush on the long press can become one of the most annoying thing. Particularly when smoothing is set high enough for eraser, one press harder and... it's not an eraser anymore. Smooth eraser (followed by the magic wand set to 128 tolerance) is way today to do a quick object separation from the background. So it happens quite often. Would be great to be able to disable this in preferences.