Why were Emerald- and Hawkins-class hulls considered as starting points for minelaying cruisers?
Short answerBecause the Royal Navy valued fast ships able to deliver large mine loads, a requirement later embodied by the Abdiel class.
NotesThe Royal Navy repeatedly explored cruisers as fast minelayers because they could carry many mines and reach a laying area quickly. Emerald- and Hawkins-derived studies belong to that longer institutional interest rather than an isolated design exercise. The desired combination was speed, payload, and the ability to operate with fleet forces. That line of thought eventually appeared in purpose-built form in the Abdiel-class fast minelayers.