I would pull the trigger if we keep Gasol or Bynum to pair with him, Gasol is the problem regarding salary and LA would need to clear room so it would be Gasol to go. Besides, he lacks the aggressiveness he had before Bynum starting asserting himself in the low post, there game is too different in many respects, Gasol can create but Bynum not so much.
Howard with Bynum in the frontcourt would own the boards both ends of the floor and while you lose Gasol's range, you force an inside out game which with Steve Nash now in the line up to match Kobe, means one on one defense and that favors LA every day of the week.
The cat that has to go is Artest, inconsistent and doesn't fit the point guard directed offense Nash will bring to the floor, he likes to create his own shot and isn't very good at it.