In order to re-fight Coronel, it was crucial that the ship’s stats for the various ships was, relatively speaking, as accurate as possible.
The word documents below cover both squadrons, von Spee’s and Cradock’s. Cradock’s squadron includes the “What if…?” variant, specifically the addition of the Canopus and Defence. Note that the Canopus has a special rule concerning its movement; this stimulates the rather dodgy boilers which plagues the ship at this period, and led to her being beached in Port Stanley as a fortified bunker.
The other thing that needs considering is the quality of both admirals. Although the Royal Navy already has a number of disadvantages, their relative qualities means that von Spee is rates +2 on the initiative dice, and poor old Cradock -1.
For the “What if…?” variant, you can argue that Cradock was not a bad admiral, he simply had poor ships. In which case you can rate von Spee at +1 and Cradock at 0.