A British Iowa class-like ship: the GB/BB/1940

Since I was young, I had this concept for a British Iowa class-like fast battleship. I am not sure just why this is true, but the way I have the ship specified in Springsharp 3.0b2 Beta, the displacement has to be quite large to have adequate hull strength. Part of the problem might lay in my protection system, with a 16ft high 16in belt. The ship has 9-16in/50 BLR, 24-4.5in DP, and 56-2pdr AA guns. The speed is 33 knots with a 12,000nm range at 15 knots. The ship would definitely be suitable for Pacific Ocean combat. This is the Springsharp report:

GB/BB/1940 Fast, Great Britain Battleship laid down 1940 (Engine 1945)

Displacement:
 55,895 t light; 58,897 t standard; 63,242 t normal; 66,719 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (886.52 ft / 880.00 ft) x 108.00 ft x (34.00 / 35.58 ft)
 (270.21 m / 268.22 m) x 32.92 m  x (10.36 / 10.84 m)

Armament:
      9 - 16.00" / 406 mm 50.0 cal guns - 2,170.00lbs / 984.30kg shells, 150 per gun
   Breech loading guns in turret on barbette mounts, 1940 Model
   3 x Triple mounts on centreline ends, majority forward
  1 raised mount - superfiring
      24 - 4.50" / 114 mm 50.0 cal guns - 50.00lbs / 22.68kg shells, 150 per gun
   Dual purpose guns in turret on barbette mounts, 1940 Model
   12 x Twin mounts on sides, forward deck aft
  4 raised mounts - superfiring
      56 - 1.57" / 40.0 mm 45.0 cal guns - 2.00lbs / 0.91kg shells, 150 per gun
   Anti-air guns in deck mounts, 1940 Model
   12 x 2 row quad mounts on sides, evenly spread
  4 raised mounts
   2 x 2 row quad mounts on centreline ends, evenly spread
  2 raised mounts
      Weight of broadside 20,842 lbs / 9,454 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 16.0" / 406 mm 610.00 ft / 185.93 m 16.00 ft / 4.88 m
 Ends: Unarmoured
   Main Belt covers 107 % of normal length

   - Torpedo Bulkhead:
  6.00" / 152 mm 610.00 ft / 185.93 m 34.00 ft / 10.36 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 16.0" / 406 mm 10.0" / 254 mm  16.0" / 406 mm
 2nd: 2.00" / 51 mm 1.00" / 25 mm  2.00" / 51 mm

   - Armoured deck - multiple decks: 7.00" / 178 mm For and Aft decks

   - Conning towers: Forward 16.00" / 406 mm,  Aft 0.00" / 0 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 263,307 shp / 196,427 Kw = 33.00 kts
 Range 12,000nm at 15.00 kts
 Bunker at max displacement = 7,822 tons

Complement:
 1,993 - 2,592

Cost:
 £30.229 million / $120.916 million

Distribution of weights at normal displacement:
 Armament: 3,863 tons, 6.1 %
 Armour: 24,182 tons, 38.2 %
    - Belts: 6,597 tons, 10.4 %
    - Torpedo bulkhead: 4,604 tons, 7.3 %
    - Armament: 4,595 tons, 7.3 %
    - Armour Deck: 7,839 tons, 12.4 %
    - Conning Tower: 547 tons, 0.9 %
 Machinery: 6,649 tons, 10.5 %
 Hull, fittings & equipment: 21,200 tons, 33.5 %
 Fuel, ammunition & stores: 7,347 tons, 11.6 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   98,156 lbs / 44,523 Kg = 47.9 x 16.0 " / 406 mm shells or 17.7 torpedoes
 Stability (Unstable if below 1.00): 1.13
 Metacentric height 7.1 ft / 2.2 m
 Roll period: 17.1 seconds
 Steadiness - As gun platform (Average = 50 %): 53 %
   - Recoil effect (Restricted arc if above 1.00): 0.70
 Seaboat quality  (Average = 1.00): 1.06

Hull form characteristics:
 Hull has a flush deck,
   an extended bulbous bow and small transom stern
 Block coefficient (normal/deep): 0.685 / 0.691
 Length to Beam Ratio: 8.15 : 1
 'Natural speed' for length: 31.78 kts
 Power going to wave formation at top speed: 56 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 10.00 degrees
 Stern overhang: 0.00 ft / 0.00 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 25.00 %,  37.00 ft / 11.28 m,  29.00 ft / 8.84 m
    - Forward deck: 30.00 %,  29.00 ft / 8.84 m,  26.00 ft / 7.92 m
    - Aft deck: 30.00 %,  26.00 ft / 7.92 m,  26.00 ft / 7.92 m
    - Quarter deck: 15.00 %,  26.00 ft / 7.92 m,  26.00 ft / 7.92 m
    - Average freeboard:  28.00 ft / 8.53 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 81.2 %
  - Above water (accommodation/working, high = better): 197.2 %
 Waterplane Area: 77,143 Square feet or 7,167 Square metres
 Displacement factor (Displacement / loading): 109 %
 Structure weight / hull surface area: 208 lbs/sq ft or 1,015 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.98
  - Longitudinal: 1.23
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is excellent
 Room for accommodation and workspaces is excellent