If going specifically only for fall coho (i.e. spawner/migrating fish not summer fish that are feeding) I'll run 2 rods with bucktails with an abalone spinner in front and a 1/4 to 1/2 ounce weight on a 3-4 foot leader to keep it from popping out of the water. Varying the distances behind the boat till you see whats working. Purple/chartreuse has always been a good colour combo for me.
Then 2 down rigger rods with spoons either behind a flasher, or (better) with a dummy flasher. Run one side down 10-15 feet so your flasher is rotating just below the surface, to help attract fish up to the bucktails, and the other side down around 30 or so.
I find the fall fish sometimes respond to weird color patterns like orange/black etc to trigger a reaction strike, and not just always your typical bait fish or krill imitations.
For actively feeding coho, I don't think anybody needs to overthink things. Put any reasonable presentation at whatever depth they are working at and you'll hook up.