Another failed attempt at Colonel Cuniberti's Ideal Battleship for the British navy

I consider that this attempt at getting Colonel Cuniberti's ideal battleship for the British navy to work in Springsharp failed, in the sense that I had to change some basic parameters to get the design to be viable. This is a good attempt, in the sense that the ship has the complete 12in belt. The speed is close, 23 knots instead of 24 knots. The changes, however, are major. I used oil fuel and turbines, and very lightweight machinery. The armament layout presented the greatest challenge, as I was struggling with stability and steadiness issues, along with hull strength and seakeeping. What I have ended up with is the best compromise that I could reach, by the time I ran out of patience. I would welcome suggestions about how to do better by experts, such as Gavin. This is the photo of the ship:

This is the outboard profile drawing:

This is the Springsharp report for my latest attempt:

Colonel Cuniberti's ideal battleship, Great Britain Battleship laid down 1905 (Engine 1921)

Displacement:
 20,781 t light; 21,691 t standard; 23,800 t normal; 25,487 t full load

Dimensions: Length overall / water x beam x draught
 523.00 ft / 520.00 ft x 88.00 ft x 29.00 ft (normal load)
 159.41 m / 158.50 m x 26.82 m  x 8.84 m

Armament:
      4 - 12.00" / 305 mm guns (2x2 guns), 864.00lbs / 391.90kg shells, 1905 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread
      4 - 12.00" / 305 mm guns (2x2 guns), 864.00lbs / 391.90kg shells, 1905 Model
   Breech loading guns in turrets (on barbettes)
   on side, all amidships, all raised mounts - superfiring
      4 - 12.00" / 305 mm guns in single mounts, 864.00lbs / 391.90kg shells, 1905 Model
   Breech loading guns in turrets (on barbettes)
   on side, evenly spread
      12 - 3.00" / 76.2 mm guns in single mounts, 13.50lbs / 6.12kg shells, 1905 Model
   Breech loading guns in casemate mounts 
   on side, all amidships
   12 guns in hull casemates - Limited use in heavy seas
 Weight of broadside 10,530 lbs / 4,776 kg
 Shells per gun, main battery: 70

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 12.0" / 305 mm 315.00 ft / 96.01 m 8.00 ft / 2.44 m
 Ends: 12.0" / 305 mm 205.00 ft / 62.48 m 8.00 ft / 2.44 m
 Upper: 12.0" / 305 mm 175.00 ft / 53.34 m 8.00 ft / 2.44 m
   Main Belt covers 93 % of normal length

   - Torpedo Bulkhead:
  2.00" / 51 mm 315.00 ft / 96.01 m 29.00 ft / 8.84 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 12.0" / 305 mm 8.00" / 203 mm  12.0" / 305 mm
 2nd: 12.0" / 305 mm 8.00" / 203 mm  12.0" / 305 mm
 3rd: 12.0" / 305 mm 8.00" / 203 mm  12.0" / 305 mm

   - Armour deck: 2.00" / 51 mm, Conning tower: 12.00" / 305 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 45,638 shp / 34,046 Kw = 23.00 kts
 Range 5,400nm at 18.00 kts
 Bunker at max displacement = 3,795 tons

Complement:
 957 - 1,245

Cost:
 £2.053 million / $8.212 million

Distribution of weights at normal displacement:
 Armament: 1,316 tons, 5.5 %
 Armour: 8,634 tons, 36.3 %
    - Belts: 2,990 tons, 12.6 %
    - Torpedo bulkhead: 676 tons, 2.8 %
    - Armament: 3,483 tons, 14.6 %
    - Armour Deck: 1,271 tons, 5.3 %
    - Conning Tower: 214 tons, 0.9 %
 Machinery: 1,572 tons, 6.6 %
 Hull, fittings & equipment: 9,260 tons, 38.9 %
 Fuel, ammunition & stores: 3,019 tons, 12.7 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   35,185 lbs / 15,960 Kg = 40.7 x 12.0 " / 305 mm shells or 6.3 torpedoes
 Stability (Unstable if below 1.00): 1.00
 Metacentric height 4.1 ft / 1.3 m
 Roll period: 18.2 seconds
 Steadiness - As gun platform (Average = 50 %): 50 %
   - Recoil effect (Restricted arc if above 1.00): 0.79
 Seaboat quality  (Average = 1.00): 1.20

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.628
 Length to Beam Ratio: 5.91 : 1
 'Natural speed' for length: 22.80 kts
 Power going to wave formation at top speed: 54 %
 Trim (Max stability = 0, Max steadiness = 100): 42
 Bow angle (Positive = bow angles forward): -2.00 degrees
 Stern overhang: 3.00 ft / 0.91 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  29.00 ft / 8.84 m
    - Forecastle (20 %): 29.00 ft / 8.84 m
    - Mid (20 %):  29.00 ft / 8.84 m (21.00 ft / 6.40 m aft of break)
    - Quarterdeck (15 %): 21.00 ft / 6.40 m
    - Stern:  21.00 ft / 6.40 m
    - Average freeboard: 22.60 ft / 6.89 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 81.3 %
  - Above water (accommodation/working, high = better): 143.5 %
 Waterplane Area: 34,342 Square feet or 3,190 Square metres
 Displacement factor (Displacement / loading): 107 %
 Structure weight / hull surface area: 185 lbs/sq ft or 903 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.92
  - Longitudinal: 2.19
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is excellent
 Room for accommodation and workspaces is excellent
 Good seaboat, rides out heavy weather easily