The flush-decked 1905 German battleship revisited

I just recalculated the German battleship design study Ger/BB/1905 with the flush deck. The dimensions were influenced by the real Westfalen class. The dimensions are 490ft x 90ft x 29ft. The armament is 8-12in/45 BLR and 12-6in/45 QF guns. The armor basis is 12in, although that is not consistently applied. The maximum speed was 22 knots. This is the new Springsharp report:

Ger/BB/1905 flush deck, Germany Battleship laid down 1905 (Engine 1909)

Displacement:
 17,805 t light; 18,579 t standard; 20,000 t normal; 21,137 t full load

Dimensions: Length overall / water x beam x draught
 490.00 ft / 490.00 ft x 90.00 ft x 29.00 ft (normal load)
 149.35 m / 149.35 m x 27.43 m  x 8.84 m

Armament:
      8 - 12.00" / 305 mm guns (4x2 guns), 864.00lbs / 391.90kg shells, 1905 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      12 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1905 Model
   Quick firing guns in casemate mounts 
   on side, all amidships
 Weight of broadside 8,208 lbs / 3,723 kg
 Shells per gun, main battery: 80

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 12.0" / 305 mm 320.00 ft / 97.54 m 17.00 ft / 5.18 m
 Ends: Unarmoured
   Main Belt covers 100 % of normal length

   - Torpedo Bulkhead:
  1.50" / 38 mm 320.00 ft / 97.54 m 27.00 ft / 8.23 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 8.00" / 203 mm 6.00" / 152 mm  12.0" / 305 mm
 2nd: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm

   - Armour deck: 4.00" / 102 mm, Conning tower: 8.00" / 203 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 34,347 shp / 25,623 Kw = 22.00 kts
 Range 4,800nm at 14.00 kts
 Bunker at max displacement = 2,557 tons

Complement:
 840 - 1,093

Cost:
 £1.704 million / $6.814 million

Distribution of weights at normal displacement:
 Armament: 1,026 tons, 5.1 %
 Armour: 7,901 tons, 39.5 %
    - Belts: 2,892 tons, 14.5 %
    - Torpedo bulkhead: 480 tons, 2.4 %
    - Armament: 2,131 tons, 10.7 %
    - Armour Deck: 2,272 tons, 11.4 %
    - Conning Tower: 127 tons, 0.6 %
 Machinery: 1,561 tons, 7.8 %
 Hull, fittings & equipment: 7,317 tons, 36.6 %
 Fuel, ammunition & stores: 2,195 tons, 11.0 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   30,661 lbs / 13,908 Kg = 35.5 x 12.0 " / 305 mm shells or 5.7 torpedoes
 Stability (Unstable if below 1.00): 1.04
 Metacentric height 4.6 ft / 1.4 m
 Roll period: 17.5 seconds
 Steadiness - As gun platform (Average = 50 %): 74 %
   - Recoil effect (Restricted arc if above 1.00): 0.68
 Seaboat quality  (Average = 1.00): 1.49

Hull form characteristics:
 Hull has a flush deck
 Block coefficient: 0.547
 Length to Beam Ratio: 5.44 : 1
 'Natural speed' for length: 22.14 kts
 Power going to wave formation at top speed: 52 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 0.00 degrees
 Stern overhang: 0.00 ft / 0.00 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  25.00 ft / 7.62 m
    - Forecastle (20 %): 21.00 ft / 6.40 m
    - Mid (50 %):  21.00 ft / 6.40 m
    - Quarterdeck (15 %): 21.00 ft / 6.40 m
    - Stern:  21.00 ft / 6.40 m
    - Average freeboard: 21.32 ft / 6.50 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 82.2 %
  - Above water (accommodation/working, high = better): 146.2 %
 Waterplane Area: 30,701 Square feet or 2,852 Square metres
 Displacement factor (Displacement / loading): 104 %
 Structure weight / hull surface area: 164 lbs/sq ft or 801 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.90
  - Longitudinal: 2.52
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is excellent
 Room for accommodation and workspaces is excellent
 Ship has slow, easy roll, a good, steady gun platform
 Good seaboat, rides out heavy weather easily