I'm actually crying a tear of joy right now. The turreted bricks are bricks no more, but actual ships !
It's 2500 meters per second, not kilometres per hour.
And slowing down to 300 m/s in 5 sek would result in around 44 G. That's should be manageable around 3300.
But afaik in this case, we riding on the super cruise shock wave and may benefiting from it's effects in this case of (de-)acceleration.
[h=2]Apparently, capital ships can finally maneuver in combat[/h]
but we already have unrealistically magical g-force tolerance for the sake of gameplay so let's not dwell on it too much.
It's not magical. We already have g-suits here in 2017. It's not unfathomable that in a thousand years g-suits would be a lot better. Your pilot wears this g-suit.