In most situations I find the Coffin Flies (spinners) are the main attraction. Be prepared to stay out late, but the big boys come out to play for these. I'm not sure in the dark the pattern has to be perfect, but my pattern has Hi Vis wings tied at a slight angle that lift off the water a bit. That really helps seeing it in the dark. Can't see a flat spinner wing, so need the wings lifted or a big post or something else to look for in the dark. Fortunately these are big spinners so you can add something substantial. Some old timers I know use a size 6 White Wulff and do well. IMHO, be really cautious of long, stiff tails as these can keep the fly from going into the fish's mouth. Sometimes you find find a morning bite downstream a bit from the night's hot spot. Those big spinners can find their way downstream over night and get some big fish up in the eddies or slow water where the spinners can collect.
Haven't had that much luck with the duns, except at Fishing Ck (limestone one). Up on the Delaware system they come off roughly when the brown drakes do and the fish prefer the brown drakes by a wide margin, so I make sure I have plenty brown drakes, but don't worry about the green drake duns. On Fishing Ck I prefer a Catskill tie. The duns seem to get up like a new born colt finding its legs. They lift up and flop down a few times before they are ready to go. I think a full hackled fly imitates that better.
Haven't had much luck on the nymphs.