When it comes to the bat weight, it is often assumed that the stronger the player, the heavier the bat should be. That is not necessarily the case. Accelerating the heavy bat will be harder than a lighter one, which means the point at which the bat will have the most force will be at the end of your swing.
But the end of your swing may not be the point at which you hit the ball. It is best to have high speed at every point of the swing. That way your performance will be consistent, even if some balls you hit a little later or a little earlier than ideal. It is important at this point to make the distinction that when it comes to youth baseball ages between 7-13, girls will need longer bats than boys usually, because girls will be taller. This means that the drop of the bat will likely be greater than for a boy of equivalent age. It is important to avoid any confusion and point out that this is not due to girls being weaker, but because the bat is longer. The net weight of the bat is likely to be the same for boys and girls of equivalent age.
When it comes to the material of the bat, most people are surprised to learn that wood is a niche option. Wood bats are normally used only if absolutely necessary to adhere to local regulations. Most bats that are used on modern baseball diamonds are non-wood. Non-wood bats usually come in one of three varieties: alloy, composite or hybrid. The first kind of bat material is alloy, predominantly aluminium. Alloy bats are the cheapest of the non-wood bats. Their main advantage is that they can be used without breaking in, as soon as you unwrap it. Another reason alloy is favored, especially early on, is due to its durability. Even if they dent, they are still perfectly playable, unless the dent severely deforms the barrel of the bat. The downside is that their batting sweet spot is much less than those of the competition, and the alloy transmits all of the vibrations from the hit right into the hands of the batter, making them less desirable for longer games.
On the opposite end of the material choices is a composite bat. These bats are made out of carbon fiber, which lends the bat incredible lightness and unrivaled weight distribution. The manufacturing process allows for a composite bat to have near-perfect weight distribution, allowing for either perfect 50-50 weight balance between the handle and the barrel, or making the bat end-loaded, giving more weight to the barrel of the bat for more power. These bats cause less vibrations to the hands and have a wide sweet spot, but need to be broken in after purchase and, if damaged, cannot be repaired. And buying a new one will be more expensive than the alloy equivalent. Hybrid bats combine the best of both worlds, with a composite handle and an alloy barrel, but keep in mind that not all baseball leagues allow for hybrid bats to be used in their tournaments.