Their needs to be the ability to make gravel from cobblestone. In multiplayer worlds such as Hermitcraft, people often complain that their is never enough gravel to make concrete or they need to go long distances for it. Finding biomes with tons of gravel is annoying and their needs to be a alternative.
Their should be some form of hammer tool or block that can turn stone/ cobblestone into gravel. Like 3 stacks of cobblestone for a stack of gravel. This would greatly balance and make cobblestone much more useful and not bother people who don't care for it.