So I own a server, hosted through ShockByte with 9gb of RAM - mc.slavcraft.net. Today we released and we have 10-15 consistent players on the server and the server TPS is around 12 at all times. We only experienced one crash and some lag among players. I got my timing report HERE, however, I have no clue how to read it.
Each and every server varies, A LOT. It is very hard to give a detailed analysis and point out the direct reason behind lag without much insight into what your server has. Given a Timings report only, I'll give you a general direction to go: It seems like in your world
factionWorld there are a lot of entities the server needs to process, and the amount is a bit too much for the server to handle.
Take a look at the most recent interval between two consecutive reports (May 17, 2020 9:22 AM - May 17, 2020 9:35 AM): In each full server tick, when the server is processing entities, it spends most of the time dealing with Blazes (on average 47.34 per tick), followed by Skeletons, Sheep and Iron Golems. All the entity types add up and at the end occupy 55.84% of one tick (that's 55.84% of 50ms). In addition to that, Server Oversleep is your second main culprit (although having significantly less impact) -- and since I do not have much experience in Paper 1.15.2 (I retrieved your server version from server list pages), I am unable to explain what this is.
You will want to take a look at the reasons and consequences behind the large quantity of mobs -- is it normal or not, why is it appearing, is it because of spawners or other plugins, should I attempt to limit them because the server is unable to handle so many, etc.
This is, of course, just a brief analysis (too brief!) of all the things that are going on in your server. I very strongly recommend checking out some basic tutorials on reading a Timings report, including the official tutorial video here. The UI has cleaned up a lot since v2's initial release, but the concept taught in the video is still the same.