They need a lot of things.
They need Rondo to be more aggressive and take more of the offensive burden.
They need KG to stay healthy and start hitting that open 18-footer (his inability to do so has really mucked up the Cs endgame offense)
They need Ray Allen, Eddie House and Sheed to at least approach last year's shooting percentages, especially from deep.
Rondo, Ray (not likely), Pierce and KG need to do better on the defensive boards.
If the players can't do the majority of those things, then, yes, I'd agree we need a trade for either more efficient scorers, better rebounders or, hopefully, both.
A trade to fix the holes on the bench. Celtics need a Jamal Crawford off the bench. Starters played well. Big3 will be fine as long as Doc limits their minutes. We need a scoring wing off the bench. And a true Point Guard so Rondo gets his breaks. I have never seen Big3 play lackadaisical. They give 100% but other guys like Sheed tend to rub their laziness on the rest off the team.
Frighteningly, Jamal Crawford has been better than Ray Allen thus far this year.