Server Ping Spikes and FPS drops

Hello! I am a moderator for a larger RP server that has seen some great success. However, we are running into some issues regarding LAG spikes and FPS drops on the server once we reach about 15+ people online at once. This is our server’s main issue as otherwise, all else seems to be fine, so getting over this hurdle would be a great benefit to us.

The only thing we’ve noticed thus far that is some clue or indication is that someone joining the server seems to temporarily spike ping and lower FPS.

Server Host Details

Location: New York

Processor: I7 Intel Core Processor

32GB of Ram DDR4 Ram

256GB of Memory

76/150000 GB of used Bandwith.

Let me know if any other information is needed, any help would be greatly appreciated.