Maybe the game engine had reached its maximum with all the weapons the concordia carried. After all, it had flak cannons, amg's, and a phase transit cannon. And amg's actually have 2 barrels per turret, you can see it in the funeral scenes. The game didn't simulate that either.
What exactly do we know about flak cannons? How do we know that they don't fire both shells at the same moment, and they sorta blend into one explosion? Come to think of it, you don't even see shells until WCA the game(where there's no Concordia) so you've got no argument. Furthermore, the neutron turrets fire two shots, yet in the engine they still count as a single weapon.
Regarding the gun limit, this isn't WC1
. There is a gun limit, but it's nowhere near as restrictive as the limit in WC1. The Connie could have several more guns... I mean, the Broadsword, for example, has three MDs, three turrets, four FFs, four torps, and one chaff pod - a grand total of fifteen. So why would the Concordia have trouble handling 12 (instead of 11) weapons?
How could the game engine be the final word in what weapons cap ships have? If you went by that then you could say the tigers claw has no weapons at all, when it actually has more than even the manual says.
What? The Tiger's Claw, according to the manual, has eight turreted lasers... which is exactly what it has in the game, too.
As for the Concordia being invincible, I think it was in some cases, (certainly there's a mission where the Bonnie Heather is invincible) but that's irrelevant - the reason the Concordia can defeat a Fralthra or two, or three, is because it has a PTC, plenty of AMGs (as opposed to the Fralthra's paltry 2 AMGs), and shields
five times as powerful as a Fralthra's. That is to say, unlike most WC2 capships, the Concordia has better shields than a WC3 fighter
.