I'm starting to think that the best thing is to take an island in each major ocean and make it a repair base. That way the ship can appear anywhere based on story needs.
I think it will have a repair system more like a mobile repair facsility. We're in our world entering an era where 3-d printing makes it super easy to get the right part and they are being considered for future space exploration. Shouldn't be that hard to use it to build a prototype and then use a base to kick it into high gear.
The way I see it, in the land of the blind, the one eye man is king. Even if this militarized cruise ship probably would get it's ass kicked by more modern militaries, the fact remains they aren't around anymore and most sunk to the bottom of the sea. Plus they have such a head start that they are a threat to any fledgling navy's.
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here's what I'm thinking for overall base level structure.
Let me know if it something in overall design doesn't work:
Deck 18 - Bridge/Island Level
- bridge at the stern that is above everything.
Deck 17 – Sea Horse Level / Wizard tower
- Small island is off to the starboard and isolated from the rest of the ship when magic goes wrong
Deck 16 – Top of Ship/flight deck
- mostly stripped down for maximum usage save the two towers above.
- helicopter pad, defensive weapons,
- pool repurposed for hover cycle training.
Deck 15 - Aircraft storage deck/Motorpool
- hanger where aircraft are stored
Deck 14 O.R.C.A. Command Main Deck Executive Deck
- where the whose/who of O.R.C.A. command have their cabins.
- staterooms for meetings
Deck 13 - Jellyfish Deck
- where the biological experiments take place.
- med bay.
- Hydroponics/food production
Deck 12 – Factory/Workshop Level
- light construction/maintence/repairs takes place here.
- also where r&d takes place.
Deck 11 – Crew Quarters
- Most O.R.C.A. rank and file are located.
- This is where the Crabs sub section is located.
Deck 10 – Training Area and Family Residences
- Where the cuttlefish ninjas are located
Deck 09 – Arming level
- Where torpedos and missiles are armed
- Also – where stealth amphibious drops occur.
Deck 08 - Training fascilities
- recruit barracks
- obstacle course.
- marching plaza replaced central park.
- gun range (replaces music hall)
Deck 07 – Storage Level
- Massive storage bay
- also where they keep their swag
- separated into locked safe areas.
Deck 06
- O.R.C.A. residential housing (low rank)
- also where the gym is.
- still need a use for the aqua-theatre.
Deck 05 - Morale/Propaganda Level
- theatre
- dips into 4th level
Deck 04 - Recreation level.
Deck 03 - panic room level
- main dining hall changed into a panic room which is heavily fortified.
- other locations are defensive points
Deck 02 – Engineering/ Reactor Level
- nuclear engine
- boiler room
- shaft alley
- Forward T.G. room
- Aft T.G. Room
- steering gear.
Deck 01 – Bilge and Ballast
- morgue / zombie storage
- also where punishment is located - "the box"
- sub /drone launch bay
- mind controlled salvage squid is located.
- also low level crew quarters