Terps....regarding positioning, that's kind of a common way to look at it. I've heard that too, terps. The things I'm writing below more importantly factor into my defensive positioning decisions.
You must know that the small forward is a super-important position (probably the most important defensive position) in the zone. It's important to have a SF that can defend, and that is versatile - which allows you to switch freely between the 3-2 and the 2-3. My SF at South Arkansas is not a great player (solid, but not great), but is still improving a lot. Hopefully by the end of the season he's a huge asset.
Remember that the DEF ratings are "averaged", so in a 3-2,
the PG, SG, and SF's DEF ratings are averaged together, and the PF and C are averaged together.
In a 2-3
, the PG and SG's DEF ratings are averaged together, and the SF, PF, and C are "averaged" together.
Just another hint - what I've learned is to self-scout.
Many coaches scout the other team, but ignore the strengths/weaknesses of their own team.
So switching based on your opponents 3pt game and reb/lp game, definitely......that's smart. However, also take into account where the strength of your own defense lies.
For instance, at S. Arkansas, my PF and my C are definitely my best players, offensively and defensively. Because of this, I'm more likely to play a 3-2 defense - my SF is more of a perimeter guy, and my PF and C can handle defending the post very well, even in a 3-2. A 2-3 will leave me burned on the perimeter against 90% of teams - my PG is a freshman and my SG is not a good defender. I use the 3-2 positioning to help them out, knowing that the PF and the C will handle the job down low.
is a link to my S. Arkansas team if you want to check it out.