A lower weight seems to mean "less likely". the elementals have a weight of 10, same as endermen. zombies, skeletons and creepers are 100, witches are 5.they have other conditions as well, such as a max light level, as well as only spawning in certain biome types, ex. BLIZZ can only spawn in COLD and SNOWY, examples of biomes in that category include IcePlains and taiga.
A buff to spawn weight would be a good idea, and if possible, adjusting which biome types the mobs can spawn in would be a fix to the other issues (which I'm not 100% sure exist yet but they seem to based on forum posts)
as far as I know though, you can't configure what types a biome belongs to, at least through the configuration files, so there may be a mod that can do it
Below is references to what biomes belong to what types:
Partially due to Biomes o' Plenty, but also due to other things, the elementals from TF who drop essential elemental dusts are hard to find.
Mob config for TF is found here: thermalfoundation/common.cfg
A lower weight seems to mean "less likely". the elementals have a weight of 10, same as endermen. zombies, skeletons and creepers are 100, witches are 5.they have other conditions as well, such as a max light level, as well as only spawning in certain biome types, ex. BLIZZ can only spawn in COLD and SNOWY, examples of biomes in that category include IcePlains and taiga.
A buff to spawn weight would be a good idea, and if possible, adjusting which biome types the mobs can spawn in would be a fix to the other issues (which I'm not 100% sure exist yet but they seem to based on forum posts)
as far as I know though, you can't configure what types a biome belongs to, at least through the configuration files, so there may be a mod that can do it
Below is references to what biomes belong to what types:
VANILLA biome list starting at line 408 in forge BiomeDictionary.java
NETHEREX![image](https://user-images.githubusercontent.com/11602945/58202146-cdc17800-7ca4-11e9-8359-4f02becbdb06.png)
I can't even hope to clear out the BoP biome categories