How capable destroyers could strengthen German surface raiding

What changes if the Kriegsmarine has destroyers with proper guns and secondary batteries?

They could escort coherent surface groups and supply ships, making German raiding operations substantially more viable.

The main gain is organizational, not a few isolated destroyer victories. Reliable destroyers in sufficient numbers could escort German cruisers and battleships through the dangerous opening and closing stages of a sortie. They could also protect a replenishment ship, allowing several major units to operate as a coherent raiding group. That task-force effect would multiply the endurance and combat power of Germany's scarce surface warships.