Since many of the servers use lobby just for transportation-related stuff, I think it would be better to disable all unwanted things that could reduce lag. For example...removing all particles, setting world borders so that terrain generation is limited etc. I am not sure whether I'm right or not. But I do know that the last time I deleted src/pocketmine/level/particles, it automatically regenerated the folder (obviously because I'm such a noob when it comes to PHP)! The question is, will deleting the particles and making the world limited reduce lag or crash the server? Also, are there any other ways to reduce lag?