My anachronisitic 3rd Class Battleship design for the Defence (Revised)

This is my anachronistic 3rd Class Battleship design for a ship built to the dimensions and displacement of the early British ironclad Defence. My greatest problem was achieving adequate stability. There are tradeoffs between the various parameters to achieve an adequate composite strength in Springsharp, along with adequate stability and seakeeping ability. Considering that the displacement is only 6,150 tons, the design does quite well. It has 9in side armour, but restricted in height. There is a 3in protective deck and a 1.5in anti=torpedo bulkhead. The armament is 4-9.2in BLR, 10-4.7in QF, and 12-6pdr QF guns. The maximum speed is 19 knots with a 15 knot cruising speed for a range of 5,750 nm. This is the Springsharp report:

HMS Defence, Great Britain 3rd Class Battleship laid down 1910

Displacement:
 5,118 t light; 5,343 t standard; 6,150 t normal; 6,796 t full load

Dimensions: Length overall / water x beam x draught
 305.26 ft / 302.00 ft x 54.17 ft x 25.00 ft (normal load)
 93.04 m / 92.05 m x 16.51 m  x 7.62 m

Armament:
      4 - 9.20" / 234 mm guns (2x2 guns), 389.34lbs / 176.60kg shells, 1910 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread
      2 - 4.70" / 119 mm guns (1x2 guns), 51.91lbs / 23.55kg shells, 1910 Model
   Quick firing guns in a turret (on a barbette)
   on centreline forward, all raised guns - superfiring
      8 - 4.70" / 119 mm guns (4x2 guns), 51.91lbs / 23.55kg shells, 1910 Model
   Quick firing guns in turrets (on barbettes)
   on side, evenly spread
      12 - 2.24" / 57.0 mm guns in single mounts, 5.65lbs / 2.56kg shells, 1910 Model
   Breech loading guns in deck mounts 
   on side, evenly spread, 10 raised mounts
 Weight of broadside 2,144 lbs / 973 kg
 Shells per gun, main battery: 80

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 9.00" / 229 mm 197.00 ft / 60.05 m 12.00 ft / 3.66 m
 Ends: Unarmoured
   Main Belt covers 100 % of normal length

   - Torpedo Bulkhead:
  1.50" / 38 mm 197.00 ft / 60.05 m 24.00 ft / 7.32 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 8.00" / 203 mm 4.00" / 102 mm  8.00" / 203 mm
 2nd: 3.00" / 76 mm 2.00" / 51 mm  3.00" / 76 mm
 3rd: 3.00" / 76 mm 2.00" / 51 mm  3.00" / 76 mm
 4th: 1.00" / 25 mm       -         -

   - Armour deck: 3.00" / 76 mm, Conning tower: 6.00" / 152 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 2 shafts, 13,563 shp / 10,118 Kw = 20.00 kts
 Range 4,700nm at 15.00 kts
 Bunker at max displacement = 1,453 tons

Complement:
 346 - 451

Cost:
 £0.483 million / $1.931 million

Distribution of weights at normal displacement:
 Armament: 268 tons, 4.4 %
 Armour: 2,379 tons, 38.7 %
    - Belts: 938 tons, 15.3 %
    - Torpedo bulkhead: 262 tons, 4.3 %
    - Armament: 515 tons, 8.4 %
    - Armour Deck: 620 tons, 10.1 %
    - Conning Tower: 43 tons, 0.7 %
 Machinery: 560 tons, 9.1 %
 Hull, fittings & equipment: 1,911 tons, 31.1 %
 Fuel, ammunition & stores: 1,032 tons, 16.8 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   8,334 lbs / 3,780 Kg = 21.4 x 9.2 " / 234 mm shells or 2.3 torpedoes
 Stability (Unstable if below 1.00): 1.01
 Metacentric height 2.0 ft / 0.6 m
 Roll period: 16.0 seconds
 Steadiness - As gun platform (Average = 50 %): 52 %
   - Recoil effect (Restricted arc if above 1.00): 0.64
 Seaboat quality  (Average = 1.00): 1.05

Hull form characteristics:
 Hull has a flush deck
 Block coefficient: 0.526
 Length to Beam Ratio: 5.58 : 1
 'Natural speed' for length: 17.38 kts
 Power going to wave formation at top speed: 59 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 4.00 degrees
 Stern overhang: 2.00 ft / 0.61 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  18.00 ft / 5.49 m
    - Forecastle (20 %): 13.50 ft / 4.11 m
    - Mid (50 %):  13.50 ft / 4.11 m
    - Quarterdeck (15 %): 13.50 ft / 4.11 m
    - Stern:  14.00 ft / 4.27 m
    - Average freeboard: 13.90 ft / 4.24 m
 Ship tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 99.3 %
  - Above water (accommodation/working, high = better): 83.0 %
 Waterplane Area: 11,167 Square feet or 1,037 Square metres
 Displacement factor (Displacement / loading): 109 %
 Structure weight / hull surface area: 104 lbs/sq ft or 510 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.87
  - Longitudinal: 3.49
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is adequate
 Room for accommodation and workspaces is cramped