What would an R-class version of HMS Vanguard look like?

How might an R-class-style, more economical variant of HMS Vanguard have measured up during the Second World War?

As a smaller mobilization Vanguard retaining the 15-inch battery, with ten twin 4.5-inch mounts and roughly 28 knots instead of the full ship's higher speed and complexity.

An R-class-style Vanguard is interpreted as a smaller, cheaper ship analogous to the relationship between the Revenge and Queen Elizabeth classes. The question's intended meaning remains uncertain, and a simplified King George V using four twin turrets is also considered. The preferred Vanguard variant retains the 15-inch battery, potentially using turrets from the old R class. Ten twin 4.5-inch mounts replace the eight twin 5.25-inch mounts, while the smaller hull reduces speed to about 28 knots. This is proposed as a mobilization variant; its wartime performance is not worked through in detail.