Hard Mob Limiter

[general]
    #Enable mob spawn limiter
    enableLimiter = true
    #If true, limits are per player cluster instead of global
    perPlayerMode = false
    #List of mob limits: [["minecraft:zombie","30"],["minecraft:enderman","8"]]
    spawnLimits = [["minecraft:zombie", "30"], ["minecraft:skeleton", "25"]]
    #Radius in blocks used for per-player cluster checks
    #Range: 16 ~ 512
    playerRadius = 128

You can set the cap to be based on a per-player basis or globally, alongside being able to change the type & number of mob that you want to limit the spawning of.

Alongside this, to avoid crowding when there are groups of players nearby to eachother, the per-player setting makes it so that it will only follow the limits of 1 player if there are several people nearby, the radius tells the mod how close the players have to be in order for it to only follow the limit of 1.

Say, for example, you installed a mod, which had some neat features but the spawn weights were all really weird & you got way more of one mob than you'd like, with this mod you can set the natural spawning to be any number you want, if you want there to be no more than 5 mobs of this type in the surrounding area? You can do that.

You're allowed to use it in any modpack you'd like, no credit needed.

Made for use in my modpack, which will be releasing soon

NOTE - Updating the mod is likely to overwrite your config, make a copy somewhere safe.