When it comes down to pros and cons, the four major pillars of discussion when comparing to aluminum are feel, performance, affordability, and safety.
Feel
Aluminum bats take away the complexities of hitting. A batter never truly understands his or her swing until they use a wood bat. Since aluminum bats do not break, players can swing at all types of bad pitches, delay reactions, or get jammed with no repercussions of damage on the bat.
Barrel size and sweet spots are minimized with wood differentiating the good hitters from the great hitters.
Aluminum bats tend to be extremely balanced and have significantly larger barrels and extended sweet spots. When swinging wood, the cut styles differ significantly enough where weight distribution and barrel size not only correlate on weight distribution but the size of the sweet spot and break points on the bat.
Performance
Aluminum bats have had more stringent regulations on their overall performance. BBCOR (bat-ball coefficient of restitution) bat regulations have shifted the technology of aluminum bats but they still take away the true feel of hitting. Some may argue that the velocity off a BBCOR is the same as wood but there are other distinctive properties that have not been changed.
The hollow center of aluminum bats and composite bats will always allow for a wider hitting area. Whereas the optimal area to hit on a wood bat, known as the sweet-spot, is typically 2”-6” in from the barrel end.
When a player learns how to hit with their wood bat, nothing will beat it for distance and trajectory. Performance related benefits extend from consistent batting practice, hitting instruction, and real game ABs (At Bats).
Metal and most composite bats lack the feedback to help you become a better hitter. The cheap hits and getting away with bad fundamentals do not help instill the discipline needed to maximize power. They become a negative reinforcement.
Affordability
Aluminum and composite bats run on average about 3 to 4 times the cost of a good wood bat. Many players replace their aluminum and composite bats every year at a cost between $300-500. Wood bats are not only more cost effective to start but if you maintain your bat well can save you a lot of money in the long run.
Safety
The safety of fielders has taken a jump to the forefront in recent years - especially for pitchers. In some severe cases, broken jaws or death have been a result from overpowered metal bats. Fortunately, the implementation of the BBCOR standards for these aluminum and composite baseball bats has made the game safer -- to an extent.
The bigger underlying issue is that the ability to modify these bats has not gone away. Shaving the inside of an aluminum or composite bat is commonplace. These changes to the bat creates a greater trampoline effect for higher energy transfer to the ball -- thus increasing the exit velocity to new levels. These modifications overcome the regulated standards and is incredibly dangerous.