Zombies - 2mal3/Minecraft-Rebalanced GitHub Wiki
Zombies (and this includes Husks and Drowned) have received a medium buff in exchange for more loot drops.
All zombies can now destroy torches and have a small chance to call other zombies for help (spawn_reinforcements). Also, ALL zombie bites can trigger hunger effect and make the zombie faster for a short time.
No real advantage or disadvantage, but zombies have a slightly random walking speed, but it stays on average at the normal vanilla value. This should split up larger zombie hordes a bit and make them more interesting.
However, for all the buffs, the loot was increased significantly, so you get more equipment and especially tridents. The already fast and difficult to hit baby zombie has also had its life halved so that it is no longer so exhausting.