The feeling around the league is that Ainge would like to make a move of some sort to bolster a team that’s been better than many expected and could, with a break or two, make a serious run in the playoffs. (“I didn’t see them being this good right now after changing three starters,” said one league exec.) It would have to be troubling for the Celtics to get on a postseason roll and be mortally wounded by a lack of experience.