"HMS Unapproachable": a new attempt

After looking at this photograph again, I decided to see if I could make a reasonable Springsharp design for the original concept: 4-9.2in, 12-7.5in, and possibly 16-4in guns. The ship is based on the sketch in Dr. Oscar Parkes' book British Battleships. The ship can fire 2-9.2 and 8-7.5 guns forward and aft, if blast effects are accepted. The broadside is 4-9.2in and 6-7.5in guns. A not-so minor detail is that the original concept may have had reciprocating engines,but I don't think that it is too great a stretch to use steam turbines. This is the Springsharp report:

Unapproachable, Great Britain Armoured Cruiser laid down 1904 (Engine 1909)

Displacement:
 14,711 t light; 15,446 t standard; 18,283 t normal; 20,552 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (572.00 ft / 565.00 ft) x 78.00 ft x (24.00 / 26.45 ft)
 (174.35 m / 172.21 m) x 23.77 m  x (7.32 / 8.06 m)

Armament:
      4 - 9.20" / 234 mm 50.0 cal guns - 380.00lbs / 172.37kg shells, 150 per gun
   Breech loading guns in turret on barbette mounts, 1904 Model
   2 x Twin mounts on centreline ends, evenly spread
      12 - 7.50" / 191 mm 50.0 cal guns - 200.00lbs / 90.72kg shells, 150 per gun
   Breech loading guns in turret on barbette mounts, 1904 Model
   6 x Twin mounts on sides, evenly spread
  6 raised mounts
      16 - 4.00" / 102 mm 45.0 cal guns - 32.00lbs / 14.51kg shells, 150 per gun
   Quick firing guns in casemate mounts, 1904 Model
   16 x Single mounts on sides amidships
  16 raised mounts
      Weight of broadside 4,432 lbs / 2,010 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 6.00" / 152 mm 410.00 ft / 124.97 m 16.00 ft / 4.88 m
 Ends: 4.00" / 102 mm 155.00 ft / 47.24 m 16.00 ft / 4.88 m
   Main Belt covers 112 % of normal length

   - Torpedo Bulkhead:
  1.00" / 25 mm 410.00 ft / 124.97 m 24.00 ft / 7.32 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 6.00" / 152 mm 4.00" / 102 mm  6.00" / 152 mm
 2nd: 5.00" / 127 mm 4.00" / 102 mm  5.00" / 127 mm
 3rd: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm

   - Armoured deck - multiple decks: 2.00" / 51 mm For and Aft decks
 Forecastle: 2.00" / 51 mm  Quarter deck: 2.00" / 51 mm

   - Conning towers: Forward 6.00" / 152 mm,  Aft 0.00" / 0 mm

Machinery:
 Coal fired boilers, steam turbines,
 Direct drive, 4 shafts, 50,795 shp / 37,893 Kw = 25.00 kts
 Range 5,400nm at 16.00 kts
 Bunker at max displacement = 5,105 tons (100% coal)

Complement:
 785 - 1,021

Cost:
 £1.346 million / $5.386 million

Distribution of weights at normal displacement:
 Armament: 1,170 tons, 6.4 %
 Armour: 5,064 tons, 27.7 %
    - Belts: 2,020 tons, 11.0 %
    - Torpedo bulkhead: 364 tons, 2.0 %
    - Armament: 1,382 tons, 7.6 %
    - Armour Deck: 1,208 tons, 6.6 %
    - Conning Tower: 90 tons, 0.5 %
 Machinery: 2,540 tons, 13.9 %
 Hull, fittings & equipment: 5,938 tons, 32.5 %
 Fuel, ammunition & stores: 3,571 tons, 19.5 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   29,620 lbs / 13,435 Kg = 76.1 x 9.2 " / 234 mm shells or 4.5 torpedoes
 Stability (Unstable if below 1.00): 1.17
 Metacentric height 4.6 ft / 1.4 m
 Roll period: 15.2 seconds
 Steadiness - As gun platform (Average = 50 %): 66 %
   - Recoil effect (Restricted arc if above 1.00): 0.54
 Seaboat quality  (Average = 1.00): 1.33

Hull form characteristics:
 Hull has low quarterdeck ,
   a ram bow and a cruiser stern
 Block coefficient (normal/deep): 0.605 / 0.617
 Length to Beam Ratio: 7.24 : 1
 'Natural speed' for length: 23.77 kts
 Power going to wave formation at top speed: 52 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): -3.00 degrees
 Stern overhang: -2.00 ft / -0.61 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 20.00 %,  24.00 ft / 7.32 m,  23.00 ft / 7.01 m
    - Forward deck: 30.00 %,  23.00 ft / 7.01 m,  21.00 ft / 6.40 m
    - Aft deck: 35.00 %,  21.00 ft / 6.40 m,  21.00 ft / 6.40 m
    - Quarter deck: 15.00 %,  20.00 ft / 6.10 m,  20.00 ft / 6.10 m
    - Average freeboard:  21.63 ft / 6.59 m
 Ship tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 93.8 %
  - Above water (accommodation/working, high = better): 168.6 %
 Waterplane Area: 32,383 Square feet or 3,008 Square metres
 Displacement factor (Displacement / loading): 125 %
 Structure weight / hull surface area: 138 lbs/sq ft or 671 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.96
  - Longitudinal: 1.49
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is adequate
 Room for accommodation and workspaces is excellent
 Good seaboat, rides out heavy weather easily