A 1908 British battlecruiser with better protection

When you look at just how bad the Indefatigable design was, especially compared to the Jane's Fighting Ships entry, you wonder why they couldn't have done better. I tried my hand at such a better design. I wanted the 9in belt and a 3in deck, in this case, along with a decent speed. My design relies on one turret being superfiring aft, and on oil-fired boilers, a big stretch. This is the Springsharp report:

GB/CB/1908, Great Britain Battlecruiser laid down 1908

Displacement:
 19,068 t light; 19,835 t standard; 21,550 t normal; 22,922 t full load

Dimensions: Length overall / water x beam x draught
 600.00 ft / 600.00 ft x 80.00 ft x 27.00 ft (normal load)
 182.88 m / 182.88 m x 24.38 m  x 8.23 m

Armament:
      8 - 12.00" / 305 mm guns (4x2 guns), 864.00lbs / 391.90kg shells, 1908 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 1 raised mount aft - superfiring
      16 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1908 Model
   Quick firing guns in casemate mounts 
   on side, evenly spread, 8 raised mounts
 Weight of broadside 7,424 lbs / 3,367 kg
 Shells per gun, main battery: 80
 4 - 18.0" / 457.2 mm submerged torpedo tubes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 9.00" / 229 mm 490.00 ft / 149.35 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 6.00" / 152 mm 490.00 ft / 149.35 m 8.00 ft / 2.44 m
   Main Belt covers 126 % of normal length

   - Torpedo Bulkhead:
  1.50" / 38 mm 490.00 ft / 149.35 m 26.00 ft / 7.92 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 9.00" / 229 mm 6.00" / 152 mm  9.00" / 229 mm
 2nd: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm

   - Armour deck: 3.00" / 76 mm, Conning tower: 9.00" / 229 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 73,360 shp / 54,727 Kw = 27.00 kts
 Range 4,500nm at 15.00 kts
 Bunker at max displacement = 3,087 tons

Complement:
 889 - 1,156

Cost:
 £1.966 million / $7.862 million

Distribution of weights at normal displacement:
 Armament: 928 tons, 4.3 %
 Armour: 6,790 tons, 31.5 %
    - Belts: 2,416 tons, 11.2 %
    - Torpedo bulkhead: 707 tons, 3.3 %
    - Armament: 1,601 tons, 7.4 %
    - Armour Deck: 1,916 tons, 8.9 %
    - Conning Tower: 150 tons, 0.7 %
 Machinery: 3,705 tons, 17.2 %
 Hull, fittings & equipment: 7,645 tons, 35.5 %
 Fuel, ammunition & stores: 2,482 tons, 11.5 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   24,423 lbs / 11,078 Kg = 28.3 x 12.0 " / 305 mm shells or 3.5 torpedoes
 Stability (Unstable if below 1.00): 1.12
 Metacentric height 4.4 ft / 1.3 m
 Roll period: 16.0 seconds
 Steadiness - As gun platform (Average = 50 %): 57 %
   - Recoil effect (Restricted arc if above 1.00): 0.66
 Seaboat quality  (Average = 1.00): 1.14

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.582
 Length to Beam Ratio: 7.50 : 1
 'Natural speed' for length: 24.49 kts
 Power going to wave formation at top speed: 54 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): -2.00 degrees
 Stern overhang: -2.00 ft / -0.61 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  27.00 ft / 8.23 m
    - Forecastle (20 %): 23.00 ft / 7.01 m
    - Mid (67 %):  23.00 ft / 7.01 m (15.00 ft / 4.57 m aft of break)
    - Quarterdeck (15 %): 15.00 ft / 4.57 m
    - Stern:  15.00 ft / 4.57 m
    - Average freeboard: 20.68 ft / 6.30 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 120.9 %
  - Above water (accommodation/working, high = better): 153.7 %
 Waterplane Area: 34,519 Square feet or 3,207 Square metres
 Displacement factor (Displacement / loading): 100 %
 Structure weight / hull surface area: 149 lbs/sq ft or 728 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.96
  - Longitudinal: 1.46
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent