Sounds like Ainge still wants to add another point guard. From the Herald:
"I’m still out there looking for another player, possibly at point guard," he said. "But I’m happy with who we’ve added so far."
He's also happy with the Scot Pollard signing (which is for the vet min according to the Globe):
"He's one of the best offensive rebounders in the game," said Ainge. "He's a terrific post defender. He has a real good feel for the game and he doesn't turn the ball over. I think he's a great teammate in the locker room. He fills a big need for us with interior defense and rebounding."
"I've always liked Scot Pollard, going back to when he was a player with Sacramento," said Ainge. "I was a big fan. I appreciated all the little things he did to help his team win."
Murphy makes an interesting observation as well:
Though not much has been said of this possibility yet, Ainge and coach Doc Rivers also consider Garnett to be part of their center rotation.
Considering the dearth of large, immovable pivotmen in the league, the Celtics probably will find many situations where they are best served by replacing Kendrick Perkins [stats] with Garnett in the paint.