maybe doubling the raririty or set in the folders to increase all mobs health or putting another mod like mo'creatures(needs custommobspawner) dartcraft thaumcraft or ars magica in it (it adds new mobs to the game) make sure to put off werewolves there very anoying because you can only hit them hard with silver or gold blades
the title looks very similar to mo'creatures you can download it and put it in the mods folder tested the same with removing mods from my modpack and it worked