A GB/CB/1915 design study

I have this design study that shows a 36 knot battlecruiser with 6-16in/45 and 12-6in/45 guns that I had called the GB/CB/1915. The ship has a tripod foremast and a tripod mainmast with a derrick. There are three circular funnels of equal height, closely spaced. By using the lightest weight machinery, I was only able to reach 35 knots with the design, but I was surprised that the design is not that far from the original, very optimistic, specification:

GB/CB/1915  Displacement=37,500 tons Standard  39,000 tons full load
  6-16in/45 and 12-6in QF guns   787.5ft x 98ft x 31.4ft deep
Cp=0.58  Cm=0.97  Hull Depth=58ft  234,000 SHP Max, 195,000 SHP normal

Weights
12,970 tons  Hull
 4,870 tons  Machinery
 1,500 tons  Aux Machinery
 1,921 tons  Armament
13,259 tons  Protection
 3,000 tons  Miscellaneous

This the Springsharp report:

GB/CB/1915, Great Britain Battlecruiser laid down 1915 (Engine 1950)

Displacement:
 34,682 t light; 36,211 t standard; 37,869 t normal; 39,195 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (793.72 ft / 787.50 ft) x 98.00 ft x (31.00 / 31.86 ft)
 (241.93 m / 240.03 m) x 29.87 m  x (9.45 / 9.71 m)

Armament:
      6 - 16.00" / 406 mm 45.0 cal guns - 2,240.00lbs / 1,016.05kg shells, 90 per gun
   Breech loading guns in turret on barbette mounts, 1915 Model
   3 x Single mounts on centreline ends, majority forward
      12 - 6.00" / 152 mm 45.0 cal guns - 100.00lbs / 45.36kg shells, 150 per gun
   Breech loading guns in deck and hoist mounts, 1915 Model
   12 x Single mounts on sides, evenly spread
  2 raised mounts
      Weight of broadside 14,640 lbs / 6,641 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 12.0" / 305 mm 450.00 ft / 137.16 m 8.00 ft / 2.44 m
 Ends: 4.00" / 102 mm 258.00 ft / 78.64 m 8.00 ft / 2.44 m
   79.50 ft / 24.23 m Unarmoured ends
 Upper: 8.00" / 203 mm 450.00 ft / 137.16 m 8.00 ft / 2.44 m
   Main Belt covers 88 % of normal length

   - Hull Bulges:
  2.00" / 51 mm 450.00 ft / 137.16 m 31.00 ft / 9.45 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 12.0" / 305 mm 9.00" / 229 mm  12.0" / 305 mm
 2nd: 4.00" / 102 mm 3.00" / 76 mm  4.00" / 102 mm

   - Armoured deck - multiple decks: 3.00" / 76 mm For and Aft decks
 Forecastle: 3.00" / 76 mm  Quarter deck: 3.00" / 76 mm

   - Conning towers: Forward 9.00" / 229 mm,  Aft 0.00" / 0 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 260,141 shp / 194,065 Kw = 35.00 kts
 Range 6,500nm at 15.00 kts
 Bunker at max displacement = 2,984 tons

Complement:
 1,356 - 1,764

Cost:
 £4.893 million / $19.571 million

Distribution of weights at normal displacement:
 Armament: 2,797 tons, 7.4 %
 Armour: 10,792 tons, 28.5 %
    - Belts: 3,420 tons, 9.0 %
    - Bulges: 1,032 tons, 2.7 %
    - Armament: 3,099 tons, 8.2 %
    - Armour Deck: 3,021 tons, 8.0 %
    - Conning Tower: 219 tons, 0.6 %
 Machinery: 6,223 tons, 16.4 %
 Hull, fittings & equipment: 14,869 tons, 39.3 %
 Fuel, ammunition & stores: 3,187 tons, 8.4 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   52,026 lbs / 23,599 Kg = 25.4 x 16.0 " / 406 mm shells or 3.6 torpedoes
 Stability (Unstable if below 1.00): 1.09
 Metacentric height 5.7 ft / 1.7 m
 Roll period: 17.2 seconds
 Steadiness - As gun platform (Average = 50 %): 53 %
   - Recoil effect (Restricted arc if above 1.00): 0.81
 Seaboat quality  (Average = 1.00): 1.05

Hull form characteristics:
 Hull has rise forward of midbreak,
   an extended bulbous bow and a cruiser stern
 Block coefficient (normal/deep): 0.554 / 0.558
 Length to Beam Ratio: 8.04 : 1
 'Natural speed' for length: 28.06 kts
 Power going to wave formation at top speed: 59 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 11.00 degrees
 Stern overhang: -2.00 ft / -0.61 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 36.00 %,  32.00 ft / 9.75 m,  32.00 ft / 9.75 m
    - Forward deck: 35.00 %,  32.00 ft / 9.75 m,  32.00 ft / 9.75 m
    - Aft deck: 14.00 %,  24.00 ft / 7.32 m,  24.00 ft / 7.32 m
    - Quarter deck: 15.00 %,  24.00 ft / 7.32 m,  24.00 ft / 7.32 m
    - Average freeboard:  29.68 ft / 9.05 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 84.1 %
  - Above water (accommodation/working, high = better): 225.7 %
 Waterplane Area: 54,062 Square feet or 5,023 Square metres
 Displacement factor (Displacement / loading): 107 %
 Structure weight / hull surface area: 195 lbs/sq ft or 954 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.94
  - Longitudinal: 1.75
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is adequate
 Room for accommodation and workspaces is excellent