What's wrong with the GENx already developed for the 747-8?
With essentially the loss of a 179-plane production order of what amounts to a military version of the 767-200LRF, there is no real incentive to build any more 767 derivatives, especially since Delta Airlines has pretty much bought all the 767-400ER’s they need to replace the L1011 and any future widebody twin sales to Delta will be either the 787-8 or 787-9.