This is a absolutly stupid idea, but why not use our past spawns and just set some kind of command block system up to make them change every 24 hours to diffrent ones, I think this is a good idea since it allows for change in the spawn and not just be one simple spawn for like eight months and then change and the whole thing starts all over again, Yes this would be a time consuming prosess to make this happen, but at the same time it lets the server constantly have a ever changing spawn!