No one would drop Dawn for Calamity. It’s giving up full uptime on 40% damage increase, and 50% damage reduction from Dark Heart rune. On the EA set you envisaged, one would use the Dark Heart rune, run with Kridershot for maintaining full hatred and then cube Aquila. Would be more effective than dropping Dawn for Calamity. As such, the 4pc DR ends up useless. (additionally, Dayntee’s Binding is one of the more frustrating mechanisms to gain damage reduction… players would be glad to go another route to gain DR)
The other thing to consider is if your set is more powerful/has enough DR and has enough utility to make it a better alternative to MS UE with Crims? The playstyle seems too similar but your set lacks sustain for discipline and there would be no effective mechanism that currently exists outside of the set to counteract this. As such, it wouldn’t be very useful for speeds/bounties and S6 and UE would remain the go to sets for DH.