Originally Posted by cxorcist
It is a true short and medium range aircraft, like the A339.
The 787-10 is a stretched 787-9, or more accurately a double stretched 787-8, i.e. a stretched ULH machine. To coin your phrase "So, that's really just further misuse of long haul aircraft". It is constrained by the 787-9 wing and gear, which constrains the range. It was not designed as a regional aircraft, that what was left over after they metaphorically "stuck a couple of plugs" in the tube.
Originally Posted by cxorcist
but the -10 would be better able to replace both 777 and A330 due to its larger capacity, pax and cargo.
Passenger capacity depends on seats used, to get 9 across in a 787 the seats would not be common (skinny) with any other aircraft in the fleet.
With a new type, comes a new simulator, a couple of new engines, other spares, additional training, etc etc. Effectively another aircraft worth of capital investment that has negative return.
Originally Posted by broadband circuit
Will it be a current 330 design, or a 350 style?
A330.