Here's what I can deduce from fighting the Antediluvians. This is against the red tempest BTW.
At the moment, the way the arcs are on the weapons, it kinda cheats. It can fire all it's weapons at you but you have a very thin sliver of a ship to aim at. Canne comment on weapon strength due to the efficiency of the tempest now at elite being 0.09 shield efficiency. They are durable though, I'll hand them that.
Thanks for posting.
The short ranged, rapid slug firing pressure turrets have an arc of 180 - 220 degrees. They are often focussed on a single broadside. Some ships only have 1 broadside. Others have two, with one lesser broadside and one main broadside. While the arcs are relatively large, the fact that they have to focus on a single broadside makes up for that. The turrets fire rapidly, but they are less effective at tracking, making them only average point defense weapons (for example: the vulcan is much more effective at PD). Constant exposure to the weapons is also required for them to do any real damage.
Missiles are high range, but slow, with hardpoints set at a 90 degrees firing angle. They are effective when launched at close range, or during an enemy flux vent. But at distances they are easily intercepted.
So no, it can not fire all its weapons at you. And if it does turn to fire, you have a bigger chance of facing its broadside, which is easier to hit, than the slim profile on its front or aft. Staying on its weaker broadside (often an unarmed one) can give you a serious advantage.
While I appreciate feedback from people fighting against the Antediluvians, I must stress that I won't try to balance against ships that are not balanced to begin with. There would be no point in doing so.