I'd like to weigh in on this. We left the Baltimore Metro league about 6 years ago, and joined an exclusively wooden bat league. I have found that it helps the good hitters, and can confuse the mediocre hitters. Let me explain.
Hitting with wood is far different, and requires keeping the hands inside as long as possible. This is a great thing for a player to learn and feel, since using aluminum is so forgiving.
However, I have found that come post-season, the players have a tendency to struggle using the aluminum. Not all, but many do. We have tried incorporating about 10 out of league games (using aluminum) in our schedule to help combat this, but we are still having the same problems.
Finally, I have had many college coaches (over the past 6 years) tell me it is next to impossible for them to analyze a player using a wood bat. The college game is aluminum, and therefore a player has a larger margin of error to work with. Quality of the wood bat material, player's hand strength, etc...all factor into their ability to use the wood.
I like the wood for batting practice and for training purposes. I just don't know if I think it is a great thing to use all the time, if they are going to have to use aluminum in the post-season.
Your thoughts are appreciated!