These are before the 80's, but my favorites are Joseph Jongen's "Symphonie Concertante for Organ and Orchestra and Camille Saint-Saenz Organ Symphony #3 "Organ". These are very difficult pieces and very beautiful. Jeremy Marchant, you make a good point, though, as to Messiaen. That was probably due more to his personal beliefs on the subject. But he is one of my favorite composers for organ literature, and his music is beautiful, but it takes a tremendous amount of skill and energy to play his literature. The Disney organ sounds good with an orchestra as does the CB Fisk in Segerstrom Center.