From what i gather the black cores was a last minute addition and they ran out of time so i imagine that will be addressed in the new year as will the difficulty balance and a few other loose ends like equipment upgrades. That being said you can find any of the bosses before your ready to fight them ( eikthyr!) so that's nothing new.

lets be objective here though. All the previous biomes had much simpler gameplay loops than mistlands. Mistlands has more weapons, more enemies and more enemy mechanics, and more options, more farmables, and more build pieces than any other biome they made. Compare the gjall to the troll or abomination or golem. This thing is like an aircraft carrier for ticks and firebombs and has a weakspot. Nothing before that was so fleshed out. Trolls had a log sometimes. The skulls and dverger camps combined with the sap root system was way more than they ever offered with any biome.

I get that the mist might have been overdone a little, or at least the tools to deal with the mist underdeveloped. That i can get. Also the Black cores need a little work. I never thought it was too hard though the spawns were a little too aggressive. The patch did overcorrect so i imagine it will go back the other way on the next one.

my feeling is that no matter what they did, just because it took a long time, some players were never going to be happy with it no matter what they achieved, which if you look at the details was alot with this update.

Me and my bud had a blast playing through so my advice is to not let your expectations get the better of you.