A no-treaty G3 follow-on combines eighteen-inch guns, speed, and protection

What might the Royal Navy build after three G3 battlecruisers if no naval treaty intervened?

Its ideal follow-on would combine twelve 18-inch guns, G3 speed, and N3 protection after the necessary infrastructure upgrades.

The answer assumes Britain has already enlarged the infrastructure needed to build and support the G3 generation. Without treaty limits, the desired follow-on would combine twelve 18-inch guns with G3-level speed and N3-level protection. That package shows how quickly displacement and cost can escalate when a navy tries to maximize all three sides of the firepower-speed-armour bargain. It also keeps dockyards and support facilities inside the design problem rather than treating the ship as an isolated drawing.