Your insistence in ducted fans or in ducted propellers is both practical and welcome. Is a much welcomed efficient invention for a given airspeed. I love it very much! Another variation: do you know that in the 30's both Russia and Germany were developing efficient steam turbines for aviation applications, and both stopped all this investments in favor of gas turbines for a speed factor (coupled evidently with the war necessities)? Much different aircraft technology will result today in the full application of steam to aircraft propulsion, including nuclear furnaces as a steam source!
Wow! At you a profound knowledge in the field of steam. But now, when I look at crash of a financial system of the world, to me come think that soon we will change on horses and bicycles. Though I would like to see steam turbines on nuclear fuel!