Most of the other top receivers from last year are back, including Brett Bartolone, Gabe Marks, Isiah Myers and Dominique Williams.
"I think our receivers have improved," Leach said.
Both the offensive and defensive lines remain a concern.
"I'd like to be bigger, stronger and older," Leach said. "We are awfully young up there."
Center Elliott Bosch, an all-Pac-12 honorable mention, is back. Defensively, the Cougars return award winners Deone Bucannon at safety, Xavier Cooper on the line and linebackers Cyrus Coen and Darryl Monroe.
Leach declined to predict if any of the 20 freshmen he signed this season will play right away.
"I've been wrong about that more than any other item I've been wrong about," Leach said. "It's like betting on quarterhorses or something.
Leach said it is difficult in this age of modern communications to disconnect from football in the off-season. He did spend some time with his kids and went skiing for five days at Schweitzer Mountain near Sandpoint, Idaho.
"The snow was bad but it was good to be out skiing," Leach said.