So basically, if the British & French governments had another brain-fart and decided in 2011 to build Concorde2, what would you keep?
Not a lot! Well maybe the pitots.
I spent a lot of time on this in the 80s, but really one has to assume that Sir Lancelot put the Philosopher's Stone in the Holy Grail and buried it under the (other) end of Finnegan's rainbow and that YOU KNOW WHERE TO DIG!
When I left it the project looked a lot like this photograph that Christiaan found and posted on another site:
About 200 PAX, area ruled fuselage, new wing planform, flaps maybe, canard/foreplane, new shorter/lighter intake design,separate nacelles, new materials (probably not composites), digital avionics etc. but most of all a revolutionary new engine concept that nobody has invented yet. This engine has to produce lots of quiet thrust for airfield operation (low specific thrust) and lots of thrust with low frontal area for cruise (high specific thrust). Any takers?
Cheers
CL