dunno really
looking into library of existing biomes (via world builder) can give you an idea what constitutes high tier and what makes a low tier
but it’s hard to say - I don’t have enough knowledge about world builder and the process of creating biomes (even though I made some), and I sure don’t know what makes a biome a low or a high tier (maybe apart from some basic things like lava on surface seems to be asigned to tier 3+, really difficult and/or crazy irregular terrain would most likely mean tier 5+)
if you simply work with world builder and create several biomes and then share them with devs, and they decide to use at least one of them, then I suppose you might be simply informed that a biome of yours is now available for in-game world generation (including private worlds) and that it’s such and such profile (for example: metal tier 4)
and not really sure it’s still a thing: considering players’ biomes for the game