I explored this years ago for my Clifton EUB - the only option was a rectangular flightcase/wardrobe! Its big, but not really very heavy...has wheels at one end, so it can dragged along behind quite easily. There are some advantages - being square makes it easy to stack in vans, so it doesn't get knocked around...its plenty big enough for "baggage handlers" to not even think about throwing it (much). Down side is it attracts interest from customs..and can be fun in airport x-ray scanners and revolving doors.
Its flown a couple of times and worked well - leave the flightcase at the hotel, and do local travel with gig bag. But its also been great for touring in vans of all sorts. Currently lives under the stairs.