Britain could build separate ironclad battle and frigate fleets

In this counterfactual, Britain would build separate ships for worldwide cruising and battle-fleet superiority. The frigates resemble later battlecruisers in role because they could force a fleeing enemy to fight, harry forces around the world, and win independent frigate actions. The two-deckers would carry battle directly to the enemy. Warrior and Black Prince could therefore retain their overseas role while the larger ships formed a concentrated battle fleet. Building both types together would announce a commitment to an ironclad navy, comparable in intent to the earlier decision to copper-bottom the fleet. The resulting navy would be more expensive, but its global and battle roles would remain distinct.