Maybe before posting your strategies you should know the rules first.
First off: convoy raids.
These happen when the affected player collects income.
So for you to be able to convoy the uk the german ships must survive the combat turn of the Uk.
Only after Uks combat move is done will the uk collect income and the opposing player can dice roll for convoy damage. This ipc is then lost and not collected by anyone.
Its also common practice to attack both fleets with subs, planes and the battleship.
The german cruiser cannot reach the uk navy as there is no naval base in berlin.