Hadlowe
Starter
The problem right now is that other point guards are lighting us up. We need both those things that you mentioned but it's also possible that we end up needing a point guard too if GV continues to be unable to stop anyone.
There are two ways to become a good defensive team. 1) You have very good inside defense and tell your perimeter to chase guys off the three point line. This results in a lot of long 2's, which is an inefficient way to score the ball; 2) you have very good perimeter D and swarm the middle on post-ups.
Right now we have neither. Cousins is the future of the franchise, so you kind of have to operate on the assumption that you are always going to have middling defense in the paint at best. This means you have to have speed and length to defend the perimeter.
Assuming Rondo comes back healthy, he would be a great step in the right direction as far as starting to defend the perimeter well. I love IT and he has played tremendously this season, but I would trade IT for Rondo in a heartbeat.