You don't? A single group can only target a single enemy. Hence, putting all PD into a single group means that even if you have 20 PD guns and 10 missile incoming, all will focus on one missile. And PD guns on different sides of the ship will not target independantly.
Which means if you have missiles coming from the left and the right, even if you have enough PD to take out all of them, you actually won't.
Can't say I agree with that.
From what I've observed, any weapon in a group set to auto-fire will fire at any valid target that enters its arc. Regardless of what any other weapons in the group are doing.
IF a target moves into the arc of more than one of those weapons in the same group, THEN they will focus on it together. Which is good behaviour tbh.
I really love the SO Dominator. I fly that ship
a lot. If what you are saying were true, it would never fire its aft & side guns at anything since the flaks are going more-or-less full time in combat. But they work just fine, and focus down any missiles or fighters that wander into range at the same time as forward facing guns in the same group are firing at something else.
I've honestly never seen the behaviour you describe despite always using a catch-all PD group. Nor have I had problems with things being ignored by grouped PD.
AI doesn't care if everything is in its group 5
This. You can put every single weapon on any ship into the same group, select an 'empty' group and let the AI auto-fire everything. And it will shoot at targets in every direction just fine.
More weapon groups wouldn't hurt. But it's not exactly a huge priority.