I miss some older shows like Lost and Heroes. Recently I would say 1899, though it was not really finished but canceled after just one season...
In regards to anime it is quite a few but mostly Ajin, Rokka no Yuusha and Houseki no Kuni. All these ended to early and had way more potential imo.
Anything fron the TLC Network before it was taken over by the sludge mongers. Secret Life of Machines, The Human Animal, The Day The Universe Changed and several others were genuinely educational. Now "The Learning Channel" pumps out some of the most horrifically braindead and stereotyped hogshit ever televised.