Enemy ships' attacks seem to concentrate on one of the ships. Depending on the enemy formationit can be any of the ships, so maybe it's better to do a fleet hp/shields instead of individual HPs.
Also, enemy health bars would be nice, but they might clutter the screen.
Does anyone remember the game much like this one - you need to build a ship out of numerous modules and the gameplay is pretty much the same, but it's not the Galaxy Siege series. Try as I might, I can't remember the name of that other game, so please comment if you know the game I'm talking about.
 "Death Squad"){kind=icon}
 "Swarm Simulator"){kind=icon}
 "Galaxy-Siege2"){kind=icon}
 "The Bravest Hunter"){kind=icon}
 "Rawr"){kind=icon}
In plans: add enemy hp bars with ability to toggle them in menu. I will rework enemies to attack multiple squad members as squad does now :)