I agree with RiP/Sharman, and all that they believe that 2-3 zone is dead. I will take it 1 step feather. For about 2 seasons i was running inside tactics for about 90% of my games. What i saw is that the guards where taking almost the same amount of shots, and some times even more than my big men. Most teams also have SG like SF, so if you combine the shots that PG/SG/SF comes from outside, then its clear that they are is no use for 2-3.
Now playing 3-2 zone on inside tactics, yes you can get lots of stops, and in general you can make it much harder for your opponent to score, BUT you get very weak on rebounding, and more often than not, your big men will be on a foul troubles early.