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The last new design for 1929, this cruiser class takes into account some of the criticisms levelled at the H class during the design process. Although generally similar, with the same 82,000 horsepower machinery, the ships have a significantly beamier hull and more freeboard.

I Class, United Kingdom Light Cruiser laid down 1929

Displacement:
7,497 t light; 7,832 t standard; 9,558 t normal; 10,939 t full load

Dimensions: Length overall / water x beam x draught
578.65 ft / 567.00 ft x 62.00 ft x 19.50 ft (normal load)
176.37 m / 172.82 m x 18.90 m x 5.94 m

Armament:
8 - 6.00" / 152 mm guns (4x2 guns), 112.00lbs / 50.80kg shells, 1929 Model
Breech loading guns in turrets (on barbettes)
on centreline ends, evenly spread, 2 raised mounts - superfiring
8 - 4.00" / 102 mm guns (4x2 guns), 35.00lbs / 15.88kg shells, 1929 Model
Dual purpose guns in deck mounts
on side, evenly spread
8 - 1.59" / 40.5 mm guns in single mounts, 2.00lbs / 0.91kg shells, 1929 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, all raised mounts
4 - 1.59" / 40.5 mm guns in single mounts, 2.00lbs / 0.91kg shells, 1929 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, all raised mounts
12 - 0.79" / 20.0 mm guns (8 mounts), 0.24lbs / 0.11kg shells, 1929 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, all raised mounts
Weight of broadside 1,203 lbs / 546 kg
Shells per gun, main battery: 200
8 - 24.5" / 622.3 mm above water torpedoes

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 2.00" / 51 mm 415.00 ft / 126.49 m 10.00 ft / 3.05 m
Ends: Unarmoured
Main Belt covers 113 % of normal length

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 3.00" / 76 mm 2.00" / 51 mm 1.00" / 25 mm
2nd: 1.00" / 25 mm - -
3rd: 0.50" / 13 mm - -
4th: 0.50" / 13 mm - -

- Armour deck: 1.00" / 25 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 82,004 shp / 61,175 Kw = 31.79 kts
Range 12,000nm at 16.00 kts
Bunker at max displacement = 3,107 tons

Complement:
483 - 628

Cost:
£2.942 million / $11.767 million

Distribution of weights at normal displacement:
Armament: 143 tons, 1.5 %
Armour: 918 tons, 9.6 %
- Belts: 341 tons, 3.6 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 148 tons, 1.6 %
- Armour Deck: 429 tons, 4.5 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 2,519 tons, 26.4 %
Hull, fittings & equipment: 3,792 tons, 39.7 %
Fuel, ammunition & stores: 2,061 tons, 21.6 %
Miscellaneous weights: 125 tons, 1.3 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
13,768 lbs / 6,245 Kg = 127.5 x 6.0 " / 152 mm shells or 1.6 torpedoes
Stability (Unstable if below 1.00): 1.29
Metacentric height 3.9 ft / 1.2 m
Roll period: 13.2 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.30
Seaboat quality (Average = 1.00): 1.38

Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.488
Length to Beam Ratio: 9.15 : 1
'Natural speed' for length: 23.81 kts
Power going to wave formation at top speed: 58 %
Trim (Max stability = 0, Max steadiness = 100): 51
Bow angle (Positive = bow angles forward): 20.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 32.00 ft / 9.75 m
- Forecastle (20 %): 26.00 ft / 7.92 m
- Mid (58 %): 25.00 ft / 7.62 m (17.00 ft / 5.18 m aft of break)
- Quarterdeck (15 %): 17.00 ft / 5.18 m
- Stern: 17.00 ft / 5.18 m
- Average freeboard: 22.51 ft / 6.86 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 99.4 %
- Above water (accommodation/working, high = better): 157.9 %
Waterplane Area: 23,170 Square feet or 2,153 Square metres
Displacement factor (Displacement / loading): 132 %
Structure weight / hull surface area: 98 lbs/sq ft or 477 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.93
- Longitudinal: 1.91
- Overall: 1.00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Good seaboat, rides out heavy weather easily

Misc. Weight includes:

Provision for 2 aircraft (only one usually carried)
8 reload torpedoes and handling gear

Looks good from here. Myself, I'd trade some of that freeboard for additional belt armor, but Britain's needs and Germany's are not the same.

I see your point on belt armour, but I'm sticking with ships that can do their job in all weathers. Having a cruiser which can withstand 6" shells is nice, but not very useful if it has been beaten off by the weather.