A battlecruiser design study

I have a pencil drawing from the early 1970's for a battlecruiser with 6-12in/50 and 8-6.7in guns. Presumably, it was intended to be German, because of the 6.7in guns. It was not intended to have particularly lightweight machinery, and didn't specify a speed, but the power. These are the incomplete specifications:

Displacement=29,000 tons
Length=730ft
Cp=0.57
Cm=0.97
6-12in/50 and 8-6.7in BLR
Power=140,000 SHP
Machinery=8,750 tons
Hull=12,180 tons
Armament=975 tons
Protection=5,750 tons
Miscellaneous=2,320 tons

From that, I hypothesized a 90ft beam and a 27ft draft. The secondary armament is in twin turrets. This is the Springsharp report:

Ger/CB/1910 Design Study, Germany Battlecruiser laid down 1910

Displacement:
 22,948 t light; 23,820 t standard; 29,000 t normal; 33,144 t full load

Dimensions: Length overall / water x beam x draught
 730.00 ft / 730.00 ft x 90.00 ft x 27.00 ft (normal load)
 222.50 m / 222.50 m x 27.43 m  x 8.23 m

Armament:
     6 - 12.00" / 305 mm guns (2x3 guns), 864.00lbs / 391.90kg shells, 1910 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread
     8 - 6.70" / 170 mm guns (4x2 guns), 150.38lbs / 68.21kg shells, 1910 Model
   Breech loading guns in turrets (on barbettes)
   on side, all amidships
 Weight of broadside 6,387 lbs / 2,897 kg
 Shells per gun, main battery: 80

Armour:
  - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 6.00" / 152 mm 460.00 ft / 140.21 m 17.00 ft / 5.18 m
 Ends: Unarmoured
   Main Belt covers 97 % of normal length
   Main belt does not fully cover magazines and engineering spaces

  - Torpedo Bulkhead:
  1.50" / 38 mm 460.00 ft / 140.21 m 26.00 ft / 7.92 m

  - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 8.00" / 203 mm 5.00" / 127 mm  8.00" / 203 mm
 2nd: 3.00" / 76 mm 3.00" / 76 mm  3.00" / 76 mm

  - Armour deck: 2.00" / 51 mm, Conning tower: 8.00" / 203 mm

Machinery:
 Oil fired boilers, steam turbines,
 Direct drive, 4 shafts, 140,428 shp / 104,760 Kw = 31.00 kts
 Range 8,500nm at 18.00 kts
 Bunker at max displacement = 9,324 tons

Complement:
 1,110 - 1,444

Cost:
 £2.286 million / $9.145 million

Distribution of weights at normal displacement:
 Armament: 798 tons, 2.8 %
 Armour: 5,754 tons, 19.8 %
    - Belts: 2,010 tons, 6.9 %
    - Torpedo bulkhead: 664 tons, 2.3 %
    - Armament: 1,186 tons, 4.1 %
    - Armour Deck: 1,732 tons, 6.0 %
    - Conning Tower: 163 tons, 0.6 %
 Machinery: 5,803 tons, 20.0 %
 Hull, fittings & equipment: 10,592 tons, 36.5 %
 Fuel, ammunition & stores: 6,052 tons, 20.9 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   42,284 lbs / 19,180 Kg = 48.9 x 12.0 " / 305 mm shells or 5.2 torpedoes
 Stability (Unstable if below 1.00): 1.33
 Metacentric height 7.0 ft / 2.1 m
 Roll period: 14.2 seconds
 Steadiness - As gun platform (Average = 50 %): 65 %
   - Recoil effect (Restricted arc if above 1.00): 0.39
 Seaboat quality  (Average = 1.00): 1.31

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.572
 Length to Beam Ratio: 8.11 : 1
 'Natural speed' for length: 27.02 kts
 Power going to wave formation at top speed: 54 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): -1.00 degrees
 Stern overhang: -1.00 ft / -0.30 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  32.00 ft / 9.75 m
    - Forecastle (20 %): 28.00 ft / 8.53 m
    - Mid (65 %):  28.00 ft / 8.53 m (20.00 ft / 6.10 m aft of break)
    - Quarterdeck (15 %): 20.00 ft / 6.10 m
    - Stern:  20.00 ft / 6.10 m
    - Average freeboard: 25.52 ft / 7.78 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 110.3 %
  - Above water (accommodation/working, high = better): 205.2 %
 Waterplane Area: 46,816 Square feet or 4,349 Square metres
 Displacement factor (Displacement / loading): 122 %
 Structure weight / hull surface area: 153 lbs/sq ft or 747 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.96
  - Longitudinal: 1.40
  - 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