This may sound crazy, but don't think either the offense or the defense is the problem.
IMO the team has not gelled, has no sense of rhythm/timing and little trust between players. I would like to see players actually move their feet! No more standing around outside waiting for someone else to make a move. Rondo holds the ball so long because no one is moving...defenses have plenty of time to get set and he has to make impossible passes. I know Ray was a three point shooter, but he was also, my opinion, one of the best movers "without the basketball." He was always cutting under the basket, disrupting defenses.
KISS (keep it simple, sweetie). Everyone needs to keep moving, cut to the basket, pass, attack. You will get baskets, and foul calls.
It is simply a matter of movement and timing. As people move, the passing will improve and the turnovers will decrease.
Even though I am not a fan of small ball, this team is too good to be so bad. I don't know if PP is injured, or just getting old, but to my knowledge no one else is playing injured now.....MOVE...run with Rondo, attack the basket, stop settling for contested jumpers!
As a tennis pro friend of mine often says, "If you want to win, you must have Happy Dancing Feet!"
Instead of letting the other team defend us, make them defend us. Our defense will improve, and has improved.