Warning message on deleting an opportunity

It doesn’t happen very often, but a few times users have hit the delete button at the top header of an opportunity when they were just trying to delete a detail line of the opportunity.  When this happens ,the opportunity is deleted along with all the tracked activities, quotes etc.  There is no message that says “Do you want to delete this opportunity?”.  It would be great if a warning or message could be added as a reminder to warn the user they are deleting the opportunity.  Or even to have a checkbox added to the preferences window where users could select to display warnings before deleting opportunities.