Vampiric Power "Blood Boil"

Hello, so I think this can go in every class category, but I will just leave it here as I play barbarian, I hope Blizzard you can read this and adjust this Vampiric Power accordingly. Blood Boil is a very nice vampiric power but please can you make this power and similar effects that give a good one time boost to trigger only with Core or other skills EXCEPT BASIC, this is such a waste of potential for cool gameplay mechanic, you can make it slower to charge or something but please make so you don’t waste it on basic attacks it’s so frustrating , you have to either stop doing everything before it charges or just randomly use it on basic skill and it’s really just a sad thing.
Please Blizzard patch this vampiric power and similar effects, there are many similar skills that work this way and it’s just wasted potential for fun combos.