If you want to explore caves how they were meant to be explored (which is not towering cobble up to get higher!), this mod takes the stage. If there's a cliff or a ledge you want to get up on, just throw your grappling hook up there and climb up! This has made spelunking a lot more fun for me, since I like to explore rather than mine a lot of the time :)
Additionally, this mod adds a few other nodes other than the ropes/hooks - The PChest is a portable inventory (which can be quite useful to store your ores on a mining trip, as well as many other applications), there's a mouth breather assembly in case you want to venture far into the ocean, and a slingshot for throwing stuff at other players/mobs!