Try the Jongens Symphonie Concertante, a fairly modern but very interesting and melodic enough piece. Dorian has a fine recording (coupled with the Organ Symphony) with Gillou and the Dallas Symphony; there's a good Telarc recording of it as well with Michael Murray. Also try the Poulenc Organ Concerto (also on Telarc with Murray). And the best plaster-cracker of them all is Pomp and Pipes on Reference Recordings, arrangements for organ and brass band that'll knock your woofers out!
Seek suggestions for mid-classic organ & orchestra
I love the organ portions of St. Saens 3rd, but there's too little of it (especially since its called the "Organ Symphony"). I'd appreciate suggestions for similar, rousing, spirited orchestral works with organ like the St. Saens or Liszt's "Battle of the Huns". I'm looking for melodic thunderous plaster-cracking stuff...I'm not into baroque organ work. Suggestions will be appreciated.