So I've thought of a few anti-grief plugins that could be created. /p toggle lava This can toggle whether u want lava on yur plot or not, and if turned on will delete all lava sources on it. /p cut (block) Allows player to cut certain unwanted blocks from their plot. And for my most impossible one at all which probably won't work is.... /p redo (player name) Deletes all changes a player has made to your plot.
Only add people you trust to your plot, so that they won't place lava, and also you can remove the lava by //replace or //replacenear; same with cut; and with the last one there should be a database for that which is exactly why we don't have a rollback plugin either, because the database gets too big and occupies too much space.