A nine-gun modernization for Renown and Repulse

Could Britain replace Renown and Repulse with better ships for the same role under treaty limits?

The better answer is to retain their speed but modernize them with three triple 15-inch, 45-calibre turrets.

The proposal retains the Renown design and its battlecruiser role. It keeps the ships' speed while increasing the main battery from six to nine guns. Three triple turrets would concentrate that battery efficiently. Guns of 15 inches and 45 calibres would provide a more powerful modernisation without abandoning the ships' defining mobility.