The Celtics definitely need some new personnel to help in the offensive end but there are some things they can do to make their offense better.
1. Give up on the "we don't need to offensively rebound the ball" philosophy and send Sully and a guard to the rim to get misses every play.
2. Quicken the pace when you have a younger set of players on the court. Fast break, get to the basket before the defense sets.
3. Once Rondo and a real back up PG are in place, drive the ball to the hole and draw charges, hit layups, or dish out for corner threes. If he is still here next year that goes for Jeff Green who should be working on using his left hand and giving left to the basket.
4.Take better care of the ball.
5. Get better defensively without needing to give up on offensive rebounds
Now, new personnel are necessary. Lee, Crawford, Wilcox, Williams, and Terry just are not good offensive fits and their defense is suspect. But doing these things besides moving some players around should help out offensively.