i had written previously that if they add/develop new biomes, they should not continue the linear power creep, where you need to visit biomes in an exact order, or else you are underleveled. in my view, everything above swamps should be flat difficulty, or very close.

starting progression:
meadows
black forest
swamps

once you get iron, the crafting really opens up, including making the big boat.

then, the "master" biomes should be about equal:
ocean, mountain, plains, mistlands, ashlands, deep north

the new root armor is a step in the right direction. instead of the next biome simply offering the next metal to obsolete all your existing gear, each of the "master" biomes should offer different types of weapons and armor, with no clear superior metal or gear. the options should be lopsided, allowing for some specialization and build-making.

ocean - kraken chitin gear. piercing weapons, improved swimming armor.
mountain - silver gear and frost gear. anti-undead weapons, cold resistance armor.
plains - blackmetal gear. good overall, no special buffs. basically, a strict upgrade over iron gear.
mistlands - spider gear. poison damage weapons and poison resistance armor.
ashlands - flametal gear. fire damage weapons and fire resistance armor.
deep north - frost gear. chill/freeze target weapon, cold resistance armor.