Secure the neck inside the case--in the event of a swift drop, that will go. Most cases have too much play in the neck, they need to be braces with foam or bubbles. Check if it possible to reduce the sideways compression of the case. You may be able to drill a tinyhole trought the flap that connects to the top and anchor it to the side with some insulated copper wire or even a nylon string Consider a cardboard box with bubble wrap inside. Don't over reinforce the box, it's just a case for the bubbles plus the extra protection of the cardboard.
For the ultimate, spring loaded case. But lots of work for that... To get on or off this list see list information at http://www.cs.dartmouth.edu/~wbc/lute-admin/index.html
