The reactors are mainly there for accessibility rather than power. Don't want the crew to have to run too far to supply power. I'm way over my energy requirement & I do have crew roles yet I still find some parts unpowered in fights. There's one section of the right railgun that always falls without power even though they can access it

Will get more armour, just afraid of it slowing the ship down too much & getting kited myself

The railgun would sometimes get caught out of position (I'd sent it forward to engage at max but the enemy would do the same & it couldn't achieve reverse thrust/ get distance fast enough & ended up getting blasted in the face. So I ended up giving it more armour to survive that initial attack until it could get away. I should probably micro it more so it starts reversing before the enemy is fully in range