A carbon post will not have near the effect of springs. Most people can't tell them from aluminum. But if your looking to save some weight they will do that. But again, few ounces of static weight is not something most people can notice.I would go with whatever keeps you comfortable for the rides that you are doing regardless of weight. You may find a modern plastic saddle that works, but it will be mostly trial and error. We've all been there. There is also no guarantee that the Swallow will break in like the Flyer did and be as comfy.