If Pegasus is more vulnerable, then it should not be called a battleship.
I respectfully disagree. The AI is really bad at using FMR. With a weak shield this ship would fall fast against Ordos under AI control.
Or enemy Pegasus dying to player's fleet after a prompt Eliminate order. Pegasus is easier to kill than other battleships. It has relatively weak firepower when the ship does not use all the missiles.
Now, Conquest is a better battleship than Pegasus. Conquest in recent releases already blurred the line between battlecruiser and battleship.
Pegasus should live up to the name of battleship, not just firepower (whether missiles or big guns) but durability too. Otherwise, buff Conquest to be the battleship (more durability, burn 7) and demote Pegasus into the battlecruiser (burn 8, more speed, mobility system) or extra large missile platform.