Not going to happen. Danny is a very patient man, and he's not the type to panic because of a losing streak. The guys who are currently under contract need to take some responsibility and play better. They're capable of great things, as they proved with the 19-game winning streak. Yes, the Celtics are flawed, and their flaws need to be addressed in time for the playoffs, but the fans and the players both need to focus on solving their problems with the guys they currently have, and avoid thinking about getting external help.
As for Gabe, I'd like to see more of him as well, but I'd prefer that he replaced TA in the rotation.