nether star and wither tools

the coper update was awesome with the new tools and the cute coper golem but why stop at coper the only use for nether stars is beacons why only have a beacon for such a powerful item make tools with special ability's like a pickaxe that can break neater blocks almost instantly but in the overworld is like using your hand and a sword that only works if you don't have a totem undying in your offhand it would do 13 points of damage so on and so forth  plus make wither tools witch give the wither effect