Out here we fish live flounder for pretty much all of our lingcod fishing. We stop to catch flounder every morning on our way out. It's a great way to get the blood flowing, get people used to the gear, and for catching lings it just can't be beat. Plus catching flounder is just fun as hell
Inshore, flounder out fishes everything bar none. We didn't used to do it as much when fishing deep water but over the years that has changed. We get em on herring and other bait when fishing Halibut, and pipe jigs will definitely get em as well. The problem with jigs is that it is so physically demanding. Most people run out of steam pretty quickly when jigging that deep. Anymore I don't run jigs on my boat hardly at all, but it does work and there is a time and place. Flounder also greatly minimizes bi catch such as yellowe eye, skate, and dog fish. Lings will eat damn near anything, including each other, but I'll put live flounder against anything out there for day in, day out lingcod fishing.
In the event of an apocalypse I'm taking a boat and some flounder gear. Won't have any trouble feeding myself, and I dunno if I could ever get sick of eating lingcod