I would like to know I can reduce lag on servers
The two biggest sources of lag that you can control both involve movement. Moving water causes a lot of lag. So ocean’s draining, water fountains and the like. The other involves the movement of mobs. In both cases, the server has to continually calculate and update the movements. Normal amounts of mobs don’t seem to be as much of an issue as farms that have tons of donkeys or dodos.
Flywheels can cause a lot of lag. Try to get rid of them.