I was watching a couple different versions of a video explanation of the warship class types at the beginning of World War II (
101 version and
deep version. I recommend both), and what I discovered about Stellaris in watching those is that they seem to have based their warship classes in large part on the dynamic in place not at the beginning of or during WWII, but shortly after World War I. Carriers were support ships, with the range of their primitive planes within the range of the opposing battleships' main guns. Those primitive aircraft were woefully undergunned to have any chance against opposing battleships or even cruisers, so they were relegated entirely to a scouting role. As carrier aircraft improved over the next 20 years or so, they improved their speed, range, and lethality against heavily armored warships, until battleships lost their ability to come close to hitting the opposing fleets and ended up being glorified anti-aircraft emplacements.
While this isn't necessarily a bad beginning for Stellaris, the issue I have is that the development paths for all of the systems are totally in parallel. While RW battleships were overtaken by the range and lethality of carrier air wings by at least early WWII, Stellaris battleships stay totally in the dominant position all the way through as SC continue to be largely toothless against anything bigger than a Corvette. Even if Stellaris SC don't get a 10:1 advantage in Hangar versus L/X-slot range, they should still easily outrange any direct-fire weapon and be able to get their alpha strike in first.
Separately, Stellaris fleets are incredibly lethal toward each other in terms of ship destruction, while RW ship-to-ship battles of WWI and WWII were rarely no-holds-barred slugfests. For example, the Battle of Jutland in WWI, between 151 British and 99 German combat ships, resulted in only 14 British and 11 German ships sunk. The great majority of ship-to-ship battle losses in the Atlantic in WWII were between U-boats and convoy escorts, with only 14 Allied and 13 Axis warships of at least cruiser size (including 1 battleship, battlecruisers, carriers, and escort carriers) sunk. Even something like the Battle of Midway only really resulted in the fleet carriers getting wiped (1 of 3 American; all four Japanese) while the remaining portions of the fleet (23 surface, 16 subsurface American; 17 surface, 13 subsurface Japanese) suffered only 2 losses and one seriously damaged. An emphasis in Stellaris on ships getting knocked out (through either hull or system damage) and then time/resource-consuming repairs would make more sense to me than outright destruction. (Although, outright ship destruction is more easily managed by Stellaris, as damaged ships aren't lost and so have to be handled differently at a fleet level for replacements - perhaps too difficult for Stellaris to figure out.)