@Jordan Essentially, all normal monsters/Monsters that are not Elder Dragons or on the level of an Elder Dragon are roughly Town Level due to scaling to Agnaktor who can cause volcanic eruptions, destroy whole villages, and increase volcanic activity in it's fights with other monsters (although monsters like Great Jaggi and the like are significantly weaker). They also scale to Aganktor's speed, which is roughly Mach 14-Mach 29 for being able to travel to Magma Chambers in a desert in about 1 second (that's 5-10 kilometers in a second)
The weaker elder Dragons (Kirin, Teostra, Kushala Daora) and Elder Dragon Level monsters (Deviljho, Rajang, some Deviants and Akantor) are to be considered Island Level due to scaling to Hellblade Glavenus, who has been stated to vaporize entire mountains with ease and because of this feat is oncsidered to be equal to the likes of Deviljho and Rajang. These monsters are Massively Hypersonic+ due to some scaling to Kirin who moves at speeds comparable to lightning. It should be noted however that Kirin should still be the fastest amongst these low-level Elder Dragons/Elder Dragon-Level monsters, but they are all roughly comparable to it due to scaling to Rajang, who can prey on Kirin.
Some of the stronger monsters (Zorah, Fatalis, Alatreon, Crimson Fatalis, Dire Miralis) are roughly Continent Level due to Zorah causing Tectonic Movement and apparently containing enough bio energy to destroy the New World according to a post previously made on this thread. The reason why all of those other monsters scale to Zorah's Continent Level is because they are supposed to be the strongest monsters in the series, classified as "Dangerous First Class Monsters".
This last part is not really confirmed yet, but we are trying to see if we can buff the strongest mosnters and the Hunter's strongest variation to Speed of Light or FTL in terms of speed thanks to Dalamadur's "meteors" coming from the sun to Earth in only a few seconds and Garuba Daora literally shooting light at the Hunter. This last part is not accepted as of yet, but we'll be working on that and trying to see what we can do.
I THINK that sums up the bulk of what we've talked about here.