Probably has to do with the fact that in the older version you could play tag with Onslaughts in an aurora, and kill them in that way. It was an absolutely overpowered beast of a ship.
Right now its still a damn fine ship, fast, maneuverable, good weapon arc spread, still good shields mid-tech shields outlcassed by an exploration cruiser.
Fixed.
PS : the Tempest and Hyperion (and many other smaller ships) can still beat an Onslaught. The Onslaught is supposed to be supported by smaller ships so that it doesn't fall for such tactics. The Aurora seems like it's supposed to be the cruiser equivalent of the Hyperion frigate, Medusa destroyer and Paragon capital ship, which are also top of the line, highest-tech pure combat ships. They all had the same shield efficiency (0.6) and they are all overpowered beasts of a ship except the 0.52 version of the Aurora.
Hyperion, frigate class, high tech, combat specialized, expensive but very powerful, 0.6 shield efficiency
Medusa, destroyer class, high tech, combat specialized, expensive but very powerful, 0.6 shield efficiency
Aurora, cruiser class, high tech, combat specialized, expensive but very powerful, 0.6 shield efficiency (nerfed to 0.8?!)
Paragon, capital class, high tech, combat specialized, expensive but very powerful, 0.6 shield efficiency
Now I might be wrong but I thought there was a pattern and that it was pretty balanced. The Aurora could be nerfed into a freighter for all I care, but that does leave a void. Will there be a new ship to fill the role of high tech, combat specialized cruiser? The role is now filled by the Apogee which has 0.6 shield efficiency, but is also specialized in cargo, fuel efficiency, crew capacity and hangar capacity. Seems overpowered.