New idea for builders and new resource rare gold and new prices for gems

My new idea for the builders is to be able to upgrade them so they build faster and a new price for gems pack cost 4.99$ for 500 gems i think supercell can make more if they resuce the price to more affordable 2.99$ for 500 gems and alter the rest of the packs as well . As for the rare gold i want this because there is a second elixr but one gold the clan castle has room for one more and this could open a new heros new barracks and much more .