The remodels are often used to justify large stat changes, but I notice a lot of gun, and later engine changes are equipment changes that can be easily swapped out.
I find that a little amusing since especially the engine changes, many would necessitate nearly a full rebuild of most ships, carefully taking it apart and putting it back together.
It would in most cases be cheaper and faster to just rip the ship apart less carefully, melt down the metal, and use the scrap to build a new ship around the new engine from scratch.
In this game however, its just a quick loadout change from the equipment menu, rapidly and easily.
I don't have a problem with it, and it makes sense from a gameplay and from how the kancolle setting works, I just find it amusing.
I wonder if the USS Ticonderoga, if its included in the game, will have a different outfit. It was considered an Essex subclass by some, and had difference in design, like internal armor layout, damage control redundancy systems being a little different, and other systems both offensive, defensive, sensor, mobility, and support. It could be used to rationalize and justify slightly changed outfits and stats, either up or down.
It also was a little top heavy due to the anti air guns, but not as much as some other ships and not to an extent that it majorly compromised seakeeping, as far as I'm aware.
Gambier Bay has a decent ASW stat, but less then one I expected for a CVE which had that as its main duty, especially compared to some other ships that had less then stellar reputations at ASW.
Though that might just be added to gear stats or more famous ships.
The Casablanca class carriers were often considered technically capable in technology, well crewed, and had good service records with effective results. They were historically also cheap to make.
Gambier's stats don't really reflect that, and her own character focuses a bit on a one note incident instead of her other success. She's also rather cowardly, PTSD riddled, and ineffective. A lot of fanfics portray Gamby as a stoic badass for what she did, which is the other direction as well. Though I suppose there are many ones that the author could have gone with besides these two characterization.
Her voice actor is also an unknown so no real star power.
In comparison, the Taiyou or Taiyo class carriers hard short careers, and didn't really get any results or successes during these careers, but have excellent stats.
Gambier Bay is unlikely to get event bonus or equipment bonus, and even with those bonus is unlikely to perform well. In the end, as a ship in this game she's not usable for hard content events as her stats are too bad. And she's also not usable for easy mode farming, as she's expensive to use despite her subpar stats. Overall she definitely isn't at risk of power creep since she was given bad traits all around.
I would suspect general Fletcher class ships might do this as well. Fletcher class is often seen as mass produced, and this is seen as a bad thing, because people assume mass produced ships are riddled with flaws and grossly inferior to super prototypes because this is a rule in so many films and manga and other series.
Historically they were considered capable, but the ships in game thus far will likely be subpar. They're definitely not as good as HMS Jervis or Tashkent in this game. Jervis has top of class ASW, special skills, and a good statline in other stats as well. Tashkent has a good statline and can equip more equipment than other ships, making her flexible and good for any situation since equipment boosts can be massive. Fletchers like Johnston are nowhere near as good as Jervis or Tash in any role, and are overall scrap or enhancement fodder. I've heard people say she might become usable with a Kai 2, but a K2 seems unlikely and hard to predict.
Johnston also notably is properly dressed in the calendar official art, but in game wears her clothes awkwardly and pulled down passed her shoulders.
The focus on ASW ships makes me wonder if some of them with more famous reputations might get better stats.
Azur Lane has USS Eldridge, less famous for combat then USS Samuel B Roberts.
Eldridge however is famous in pop mythos and films, being in the urban legend, the Philadelphia Experiment.
In Azur Lane she's got relatively good combat stats for her type, and also has a 'Philadelphia Experiment' stealth/teleporter system that boosts her evade by a lot in game.
Other ways to interpret the urban legend are in pop culture. Metal Gear Survive has it as a wormhole generator to another dimension. Other series attach other attributes to it like area of effect weapons, illusions, mind control, or other fantasy elements and super powers.