The Dons boss praised "brilliant" Brewster's final contribution to the Dons.
"I think young (Chris) Hogg learned a lot playing against him," Calderwood said.
"We have got other players. Lee Miller was unlucky, he was brilliant at the end of the season. Steve Lovell is there and wee Chris Maguire is champing at the bit although he is a different type of player.
"That's why we brought 'Brew' in - to learn from him. We will see how it goes, there is still a bit of talking to be done."