There just aren't very many ways to say it at least from my point of view, but Stonefist just absolutely should not have a cast time on it. A Class spammable ability is completely pointless if not only does it have a cast time, but its' first attack is just an AoE stomp that isn't even the part of the ability that stuns enemies. They either should remove the cast time or increase the damage of Stone Giant by at least 5% and make the opening stomp the part of the ability that stuns enemies.
Murphy's Law of PvP : If it can be abused and or exploited, it will be abused and or exploited.