Hill isn't a bad defender...he's just not spectacular. One of the things he can do well which will help our defense is change ends quickly. Pau doesn't do that well when he's hurt (but nor does 99% of the NBA). Kaman can't rotate quickly to cover shooters or protect the rim...
Does that not remind a lot of people of Marc Gasol? How did MEM become a good defensive team?
Playing defense well as a team requires having a game plan that everyone knows like the back of their hand and STICKS to. There are a PLETHORA of defensive schemes that can hide either Kaman or Pau in a halfcourt set. The problem we are going to have is when we have to play them TOGETHER...that's when we need to out rebound everyone by at least 10rpg to have even a slim chance of being a mediocre defensive team.
Hill+Pau OR Hill+Kaman = GOOD
Pau+Kaman = BAD
Si, Si, Si.