Good update.
As for my comparison, perhaps it wasn't a good one. I was aiming to compare it to ships of similar DP allotment since I haven't seen any other battlecarriers at 55-60 DP other than the Matriarch, and that one feels more pure carrier than a hybrid. Regardless, the general trend seems to be that the more carrier-esque a ship is, the more restrictive its OP.
To prove this point, let's look at some 4-bay battlecarriers:
Legion: 260 OP.
Legion XIV: 270 OP.
Kurmaraja: 240 OP.
Keto: 190 OP.
Castella (LI): 240 OP.
Hresvelgr (RG): 240 OP.
Ingress: 240 OP.
Filament: 360 OP.
Then, for even more comparison, you can look at the relationship between a pure battleship (Onslaught) and a battlecarrier (Legion) and see what vanilla's OP allotment is for both these ships at 40 DP:
Legion: 260 OP.
Onslaught: 360 OP.
Both of these ships share a lot of similarities. They have the same system. Similar slow speed and heavy armor. Similar mounts.
But Legion has 4 fighter bays. For this big difference, the ship was given 100 less OP.