Slightly two-pronged, this.
First, a cosmetic issue -- the tooltip that appears when you select an entry also pops up in odd places when the mouse hovers over empty space in the lower part of the window.
The request part of this -- it'd sometimes be useful if an entry could be deactivated or suspended instead of just deleted.
The tooltip is not something I can control (AFAIK). It gets activated when an item is selected, but it appears anywhere the mouse is moved to as long as the item is still selected. I'll do some research and see if it's meant to do that or not.
I've had the idea of a checkbox to enable/disable the items in the back of my mind for a while. :)