I too was unsatisfied with touring using standard frames, racks and panniers, so I am currently in the process of building all of them mostly from scratch. I am a real DIY enthusiast, so you may not want to go my way, because there's a ton of work involved, but there is a middle ground to be found.
First of all, the frame. If you want a longer frame without reaching Big Dummy/Xtracycle total length, I would recommend the Kona Ute. The rack is a lot longer, it's built in the frame, but it's about 20cm longer overall than a standard bicycle, as far as I can tell from the pictures.
Some people suggested a trailer, but you really should try one before. I rode a bicycle with a loaded extrawheel-like trailer and didn't like it at all, it was always pulling to the sides, but the guy who had it really liked it. It may be practical, but it is strongly dependent on personal preferences.
As far as panniers go, you should really look into making your own or having some made for you. Commercial offerings are far too general in order to work with as many bicycles as possible. You could easily have panniers that are aerodynamic, as large as you need and are easy to get on and off the bike, but nobody makes them, so you have to do it. Also, the large rack of the Ute allows for some creative pannier design, and you could put a lot more weight on the rear rack because the longer wheelbase puts your weight closer to the front wheel than on a standard bike.
Bottom line: there are better ways to carry stuff, but the fact that you also want your bike to be car/plane/train friendly calls for some big compromises if you stick to the off-the-shelf panniers. You really have to go the custom or diy route in order to have a set of panniers that work for you, considering your rather conflicting requirements.