Hi Folks!
Glad to hear that stuff that was already posted qualifies, so here's my three cents:
1. Rotterdam-Class (Netherlands)
During the mid-twenties, the Dutch, who had pleaded to provide a credible defensive force for their east Indies possessions to the British and the US in exchange against guarantees from these powers to coming to their aid in case of a Japanese attack, were looking for an affordable heavy cruiser design to be license-built at De Schelde in Flushing and Fijenoord in Rotterdam. Germany was still banned from the international arms market, but Blohm&Voss set up a subsidiary company in Rotterdam, which eventually won the contract by downscaling the existing I/10 design to 9.500 tons and accepting Bofors guns as main armament (Vickers had tried to sell a modified County-class to the Dutch, but wanted to supply the guns itself). The ships were laid down in 1925 and 1926 and completed in 1928 and 1931, respectively, the delay being a result of the Great Depression. They were named Amsterdam and Rotterdam. They carried eight very powerful 203mm guns, but only scant protection and a bare-bones secondary armament of seven 75mm guns and six 533mm torpedoes. Propulsion was provided by two sets of Parsons turbines with six boilers and 60.000hp plus two MAN cruising diesels with 13.500hp; top speed was 32 knots. They received airplanes in 1933 and 1935, exchanged four of their seven 75mm guns with 40mm Bofors twins in 1936 and 1937, and swapped their remaining 75mm guns for Bofors 105mm twin heavy AA mounts in 1938 and 1940, respectively, at that time also receiving a completely reworked fire control suite.
2. Craigmiadh-Class (Thiaria)
Plans to build Thiarian heavy cruisers were made since the mid-1920s. The first study was a wholly unarmoured ship with only six heavy guns which would conform (with some cheating) to the 6.000 ton limit; even then, the main guns were limited to 195mm caliber. Guns of this caliber were in use in the Thiarian navy since the 1900s; they had equipped a battleship, two armoured cruisers and nine coastal artillery batteries with a total of 54 guns. Their 105kg shells were considered exceptionally powerful, and there were still over 2.000 of them on storage. Although the 6.000 ton heavy cruiser project was dropped in 1928, development of an all-new 195mm gun with a sliding wedge breech for high ROF was continued anyway. When Thiaria was again admitted into the club of naval powers at London in 1930, they were granted 45.000 tons of heavy cruisers. The optimum way of utilizing this tonnage was - obviously - to build five 9.000 tonners. As most early US treaty cruisers were rather light and came out significantly below the 10.000 ton limit, construction of a reasonably balanced heavy cruiser on this tonnage seemed feasible to the Thiarians. Now the existence of a 195mm gun, which was considerably lighter than every foreign 203mm piece, proved beneficial. Within six months after signing the LNT, a 9.000-ton heavy cruiser designed around three 195mm triple turrets was presented to the naval staff for approval. The ship looked outwardly quite similar to the Urgharda-class, with a short tripod mast forward and a big one aft, two widely spaced funnels and a clipper bow. General appearance of the design reminded of contemporary Italian cruisers - essentialy a mix between the light Raimundo Montecuccoli and the heavy Bolzano - but the hulls were sturdier and beamier, and the superstructure looked more massive, with the funnels being of equal height and width. Unlike the Urghardas, the new heavy cruisers had catapults and aircraft hangars from the start, although the Thiarians did not yet have the required small scoutplanes; of the rather heavy French flying boats used instead, only one rather than the specified three were embarked, because it did not fit into the hangar. These cruisers were the first Thiarian ships with wholly domestic Thiarian machinery; unlike the Urghardas, which had all turbines amidships, the twin-shaft plant of the new heavy cruisers was arranged in two independent units of one turbine set and four boilers each, protected by transverse bulkheads and void spaces. 80.000 hp developed a design speed of 32 knots; although they were a thousand tons lighter than the British County-class ships, they were half a knot slower with the same designed hp due to the shorter hull. Designed range was 10.000 miles at 15 knots, which was necessary for raiding; they proved economical steamers in service, even with dirty hulls. Apart from their nine 195mm guns, they carried six 100mm flaks in three twin mounts aft, ten semi-automatic 37mm twins, six quad 13mm machinegun mounts and twelve 559mm torpedo tubes in four triple sets. Protection was improved compared with the light Urghardas, with an 80mm belt covering a relatively large part of the hull and a complete armoured deck of 40mm. They were reasonably safe against 152mm shells, but not against 203mm ones; this was deemed acceptable, because neither were most foreign 1920s heavy cruiser designs. All things considered, the Thiarian heavy cruiser was a well balanced warship with no outstanding features, but also no particular weaknesses (apart from the rather large tactical diameter due to relatively small rudders).
3. Almirante Abreu-Class (Brazil)
Brazil's cruiser force faced block obsolescence in the early 1930s, just when the Thiarians and the Argentines started to gear up and order heavy cruisers. In order to acquire sufficient numbers of cruisers, limited size was considered acceptable; four units of a balanced and affordable design were considered more useful than only two of a high-end one. Thus they specified 8.500 tons maximum size, 32kts speed, at least six 203mm guns and protection against this caliber. Armstrong met these specifications with a modified Apollo-class hull, which - apart from the missing superfiring turret aft - was hard to distinguish from a standard Apollo from a distance. With their 114mm belt plus armoured boxes over the magazines, they were well protected; they also were rated seaworthy and comfortable. Their main armament was augmented by 8 102mm HA guns and three quadruple pompoms; eight 533mm TTs and two fixed catapults (arranged as on HMS Exeter) were provided. Two were built in Great Britain from 1933 through 1936, two more in Brazil from 1935 through 1940.
If I can scratch together some time, maybe I try something new... I have an idea for a contradiction in terms, a 1930s Japanese cruiser adhering to the WNT size limit.
Greetings
GD