Andy Farrell says England have a "feast" of players to choose from as they rebuild after the World Cup.
But Farrell, a member of Stuart Lancaster's new-look coaching team, is warning players that they will have to work hard to win selection.
"Nobody gets a cap if they aren't ready. We've got to make sure the balance of the team is right," he said.
"It's a fresh start for everyone with some exciting players to choose from. It's a feast for us at the minute."
Farrell, who will take time out from his job as first-team coach of Saracens to help guide England during the Six Nations, says there are a number of big games coming up in the Premiership and Heineken Cup in which players can stake a claim for the national side.
But the former dual code international said one of the main considerations will be picking players who can gel as a unit.
"We've just got to get it right," he said. "You can't have 15 individuals out there on the field."
Farrell joins scrum coach Graham Rowntree in Lancaster's coaching set-up.
They have been given temporary responsibility for the England team while the Rugby Football Union looks for a long-term successor to Martin Johnson, who stepped down after a disappointing World Cup.
The Six Nations gets under way in February. England, who won the 2011 tournament, start against Scotland at Murrayfield on 4 February.