Don't forget that the pike's consumption is spread throughout the year - during which time the prey fish GROW. Also, some of the fish pike eat are other pike.
Pike and all the other fish have adapted to live in balance since long before they followed the retreating ice to these parts.
Man's attempts to "improve" on nature by stocking extra fish into established communities usually prove to be an expensive waste of fish, effort,and time; the Aquarists' motto of "look after the water and the fish will look after themselves" is pretty sound.
If you're starting from scratch, and want a sustainable community of fish, get in an expert - the EA should be able to point you at some - and work out what you want, and how to acheive it - the freshwater food chain is very complex, and you'll have fewer disappointments if you get the plant and invertebrate communities established first.
Once it's up and running, don't forget that freshwater communities are dynamic, flexible and productive. Don't be scared to remove SOME fish and plants. But keep a careful eye on how the community responds when you do.
Some of the best roach and pike fishing ever was in the Hampshire Avon when it had clear water, copious weed growth, regularly cut and removed, and when many stretches were preserved for game fishing, so many pike and roach were removed.