A german cruiser in 1912 would probably be both coal and oil fired going by what they did in OTL. And i believe that transom sterns were something that came after WW1 but im not entirely sure, still i believe that a cruiser stern is more historically accurate.
On the offchance that you might be right, I reworked the design. Honestly, I'm not as happy about the increased size, but I was able to make it half-coal/half-oil, eliminated the transom stern, covered the entire engine room with armor, and even managed to get a half-knot of top speed and cruising speed out of it.
SMS Wittemberg, German Empire Burgencruizer laid down 1912
Armoured Corvette (Broadside ironclad)
Displacement:
10,944 t light; 11,239 t standard; 12,461 t normal; 13,438 t full load
Dimensions: Length overall / water x beam x draught
559.55 ft / 550.00 ft x 62.00 ft (Bulges 64.00 ft) x 21.00 ft (normal load)
170.55 m / 167.64 m x 18.90 m (Bulges 19.51 m) x 6.40 m
Armament:
2 - 5.90" / 150 mm guns in single mounts, 102.69lbs / 46.58kg shells, 1912 Model
Breech loading guns in deck mounts
on centreline ends, evenly spread
8 - 4.10" / 104 mm guns in single mounts, 34.46lbs / 15.63kg shells, 1912 Model
Breech loading guns in broadside mounts
on side, all amidships, all raised mounts
Weight of broadside 481 lbs / 218 kg
Shells per gun, main battery: 150
2 - 19.7" / 500.38 mm above water torpedoes
Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 12.0" / 305 mm 405.90 ft / 123.72 m 9.45 ft / 2.88 m
Ends: Unarmoured
Main Belt covers 114 % of normal length
- Torpedo Bulkhead and Bulges:
2.00" / 51 mm 405.90 ft / 123.72 m 19.71 ft / 6.01 m
- Armour deck: 5.00" / 127 mm, Conning tower: 12.00" / 305 mm
Machinery:
Coal and oil fired boilers, steam turbines,
Geared drive, 4 shafts, 66,448 shp / 49,570 Kw = 28.50 kts
Range 4,000nm at 16.00 kts
Bunker at max displacement = 2,199 tons (50% coal)
Complement:
589 - 766
Cost:
£0.822 million / $3.289 million
Distribution of weights at normal displacement:
Armament: 60 tons, 0.5 %
Armour: 4,921 tons, 39.5 %
- Belts: 1,904 tons, 15.3 %
- Torpedo bulkhead: 592 tons, 4.8 %
- Armament: 0 tons, 0.0 %
- Armour Deck: 2,285 tons, 18.3 %
- Conning Tower: 139 tons, 1.1 %
Machinery: 2,776 tons, 22.3 %
Hull, fittings & equipment: 3,188 tons, 25.6 %
Fuel, ammunition & stores: 1,516 tons, 12.2 %
Miscellaneous weights: 0 tons, 0.0 %
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
17,177 lbs / 7,791 Kg = 167.3 x 5.9 " / 150 mm shells or 3.0 torpedoes
Stability (Unstable if below 1.00): 1.27
Metacentric height 3.8 ft / 1.2 m
Roll period: 13.8 seconds
Steadiness - As gun platform (Average = 50 %): 76 %
- Recoil effect (Restricted arc if above 1.00): 0.05
Seaboat quality (Average = 1.00): 1.08
Hull form characteristics:
Hull has a flush deck
Block coefficient: 0.590
Length to Beam Ratio: 8.59 : 1
'Natural speed' for length: 23.45 kts
Power going to wave formation at top speed: 57 %
Trim (Max stability = 0, Max steadiness = 100): 70
Bow angle (Positive = bow angles forward): 10.00 degrees
Stern overhang: 5.00 ft / 1.52 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 25.80 ft / 7.86 m
- Forecastle (13 %): 16.42 ft / 5.00 m
- Mid (50 %): 16.42 ft / 5.00 m
- Quarterdeck (13 %): 16.42 ft / 5.00 m
- Stern: 16.42 ft / 5.00 m
- Average freeboard: 16.91 ft / 5.15 m
Ship tends to be wet forward
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 113.5 %
- Above water (accommodation/working, high = better): 126.5 %
Waterplane Area: 24,708 Square feet or 2,295 Square metres
Displacement factor (Displacement / loading): 114 %
Structure weight / hull surface area: 85 lbs/sq ft or 416 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.97
- Longitudinal: 1.03
- Overall: 0.97
Caution: Hull subject to strain in open-sea
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform