I think Guy Gardner doesn't die in a blaze of glory, I think he dies in a bar fight. He's maybe getting older, maybe looking at a gold watch and forced retirement out of the Corps, and he goes out for one last drink before he loses the ring. He's getting piss drunk and dreading the idea of a quiet retirement on earth with no purpose and no Corp to serve and he decides that, like everything else, he's going to do it on his own terms. So he finds the biggest, meanest mofo around (Lobo maybe?) and smashes a bottle off the guy's head, causing the whole place to erupt in violence. Guy dies on the floor, covered in blood and beer, with a cigar stolen from Lobo in his teeth and a smile on his face.