Suggestion: Make the ancient crystals' benefits (chance to land The Primal Rage or Fangs of Fury) as passive abilities, and remove the crystals. And grant both sets of benefits to all ancients. It will help remove the faction from the combat style equation (which I have made detailed points about in other threads).
If they will do this, you will still get your benefit of the ancient combat crystal as well as use one of the epic claws. I'm hoping this idea is considered. Allowing both sides the use of either elemental breath attack was the first half. This idea is the logical second half.
If they choose to make it a crystal no matter what, so that the player is forced to decide whether to use the crystal or an epic claw (bad idea since being ancient should have inherent benefits, not ones I have to give up something else for), then another solution would be to add both sets of benefits to both crystals, and then changing it into a jewelry crystal for use in a headscale.
But the better solution is make them passive abilities. AFTER they finally get the delay modifiers fixed again on The Fangs of Fury.