However, they are, imo, touting N52 Etrigan to be more powerful than he was in previous continuity. He's been confirmed (in 2 different issues now) as one of the mystical beings that battled Cain thousands of years ago (and N52 Cain is a BEAST.) That said, I could see Etrigan displaying power that puts him above Atro, down the road.
__________________
"I am tired of Earth. These people.
I am tired of being caught in the tangle of their lives."
Meanwhile Atrocitus has weakened due to a lack of rage following Krona's death and the destruction of the central battery. However even in a near dead state he ripped through space/time to reach Stormwatch HQ in hyperspace.
__________________
"And then there was nothing. A once broken something now void.
And on the first day, Doom spoke... 'Be.'
And then there was life."
Pre-reboot Etrigan was shown several times to be on or near pre-reboot Supes' level in power and durability. he one-punched Supes to the moon and took it to Lobo (and took what Lobo could dish out) in a great series.
New 52 Etrigan is supposed to be more powerful with a lot more potential, while Atroc is a bit nerfed.
I don't think Atroc will affect the demon with much more than constructs, and those are suspect against someone of Etrigan's strength and with the hellfire attack.
realistically speaking Etrigan was a demon who was able to at least contend in the same arena as Morgaine and Merlin as he was someone Merlin felt could deal with her or at least be a significant force against her. So that gives him some extra credit in my book.