The Repose Mod is an interesting one that restructures the way blocks like dirt, gravel and sand behave in the game. They no longer stack as easily when placed and crumble just as easily when certain lower blocks are removed.
These sensitive blocks are much more susceptible to falling over when placed on top of a similar block. If you stack dirt on top of sand or gravel or even clay it will fall to the block below it. They function more like an avalanche now but are much more natural and realistic in a way.
This mod adds a new level of difficulty to the game that forces you to pay closer attention to the world you’re digging up. You may want to think twice before breaking certain blocks or you may end up buried. The plus side being that it will certainly make removing those large gravel pockets much quicker.
If you’re looking for a new challenge in Minecraft, give this one a shot but you might want to start a new world or you may end up ruining a good save. You will need an additional API to run this mod found here.