Renewable Cinnabar

This is a very straightforward mod to make cinnabar renewable, since it isn't in vanilla. When lava pours onto water from above, if the water block has potent sulfur directly beneath it, it'll turn into cinnabar instead of stone. This means it's easily farmable with existing stone generator designs, and the new-update-resource-hunting adventure is preserved since you need to go out and find some sulfur to get started.