Welp, 200th page of the forum, may as well talk about my experiences playing this game.
The first thing I have to point out is just how many 'gotchas' there are. Things you either don't see coming and get blindsided by, or that tends to go unnoticed without looking through the codebase or forums.
Once, I lost a lvl 205 hardcore character to a manticore transformation. I had been experimenting with the different races, trying to see which racial perks stuck around after I was no longer qualified as that race ('Greedy' from Tanuki and 'Incorporeality' from Ghost stayed, so that was a pattern). My character had ended up with both a penis and a manticore tail, promptly stuck one in the other when I dismissed it as just another negative racial modifier, and bad-ended. That was fine, I had clones... except I didn't get a chance to metamorph the penis away; my four clones all bad-ended the exact same way the instant I popped into them, without giving me an opportunity to do anything, and my hardcore save went bye-bye. I was a bit salty about that, I have to admit.
I'm not yet into the part of game play where I know what everything does, so when I encounter something that locks me into a race or keeps me from transforming more, I become very leery. I haven't yet tried to see what the Racial Paragon like of perks do, for example. Also, I had to experiment with not bonking the Elven Hunting Party and submitting instead, then not selecting 'Need2Go', before I even realized that the Elven Village was a button in the Places menu.
Another example of a 'gotcha' is what the 'human' race does to XP training speeds. Primaris Super Human is absolutely essential for training combat - with it, I can level a combat skill like Dao of Large Weapons or Dao of Swords to the max level of 150 in short order with only low amounts of training-dummy attack-spam. But if I don't have the Primaris Super Human buff to EXP? Say, if I'd gotten the Human Supremacy perk that adds a second mutation slot per body part, plus the Munchkin hidden job which adds a third, then started collecting them all, then realized that each level of a mutation adds a -1 to Human racial score and it's not possible for me to count as Human any longer? (Yes, this actually happened to one of my characters.) Then, combat training xp slows down to an absolute crawl. Worse, Human Versatility's EXP multiplier boost to utility skills doesn't take effect if you don't have 18 Human score, so my ability to train Alchemy and Mining went poof, too.
As a side note, if you don't have two vials of E-Ichor to get an internal mutation without meeting the racial requirements? Human mutations need you to have 17 Human score. So, if your first mutation isn't a 'human' mutation, you're locked out of getting ANY human mutation. (To my knowledge, Evangeline never says in her dialogue that using two vials of E-Ichor at once will bypass the racial requirements, and I hadn't yet found that tidbit in the forums or wiki, so the character that did that was straight up deleted in disgust.)
And let's not forget how esoteric getting E-Ichor is in the first place, because it's available from exactly one place, the Dilapidated Shrine in the Battlefield Boundary (NOT the Outer Battlefield). Not only do you have to grind up Evangeline's affection before this random dialogue option unlocks, you need Chilly Peppers to have even a chance at getting E-Ichor, and it's around a 10% chance per 3 peppers. So grinding Winter Wolves in the Glacial Rift isn't even practical; the only way to get the stuff in any quantity is to spend thousands of spirit stones on Chilly Peppers in the HeXinDao TF/Exchange shop to throw away for the gamba.
And wouldn't you know it, Diluted E-Ichor is the only item that gets accepted as the Ingredient 1 when making Stat Pills! If you haven't yet figured out how to grind for ludicrous amounts of gems (Ebon Labyrinth, yo), then the only way to bump up your Mutagen Stat multipliers is by cramming dozens of TF items down your throat.
Side note on Stat Pills, the herb required for each stat is a little unintuitive. You'd think Blade Ferns are what's used for Strength pills, and Iron Weed for Toughness pills, right? Well, nope. Iron Weed is for Strength, Blade Ferns are for Speed, and Toughness needs Healing Herbs. At least Moon Grass for Wisdom makes sense.
Incidentally, what is Ginseng used for? I haven't yet dug through the codebase to figure that out. It certainly doesn't seem to be used as an Alchemy ingredient, despite the item description referencing just that.
Now on a more unrelated note, there's the cultivation lectures. I wasn't interested in the HeXinDao arena for a while due to wanting to level up first, and that meant that on my first few attempts, I got waaaay too far before realizing that Miss Akemi's lectures were open to even new characters... and that that was the only way I could really start 'cultivating'.
It goes on. I haven't yet figured out how to recruit Chi Chi. I haven't yet managed to unlock the World Tree. I can't figure out how to tell which of physical/magical/lust damage Lethice is weak to, so I haven't beaten her yet. When I found Celess Jr's legendary items menu, I had to dig in the codebase to figure out what each item did, because I in no way had enough Radiant Shards to experiment. Not knowing my current max Alchemical, Mutagen, and Knowledge Stat modifiers means I keep having to throw away a few gems on extra boosts every time I want to max it out again - which isn't truly harmful, but is still annoying. I had to dig through the codebase to figure out which pieces of equipment the Aether Twins needed to eat to evolve, because there's no greyed out buttons for the equipments that COULD be fed, but I don't currently have in my inventory - please, add a dialogue button that lets them give 'hints' about an equipment that can be fed at their evolution level. I had gone through the Hidden Cave with the Dragon Boi four separate times on four separate saves before I went in there with alembic and furnace already purchased and realized that I could pick up an upgrade to the alembic and furnace there, and now there's no real way to know what other upgrades are hiding from me without digging through the codebase, because there was no text prompt about "There's some good-quality alembic parts in this crate. Perhaps if you had an alembic yourself you could scavenge these for an upgrade?" or something like that. The buttons that you pick Hidden Jobs with in the Super Perk Up menu don't have any text about what their perks do unless you already have a spare super perk point, you have the required level, and you've unlocked the previous tier... so you can't really plan out a build unless you go through the codebase (the wiki isn't updated with all the hidden jobs and what they do). Luna locking out other NPCs when she gets too yan-yan is annoying enough that I tend to block her from appearing - and that was buried in a submenu somewhere, so I didn't realize I could do that at first. The time-gate between Metamorph and Metamorph EX is... likely unnecessary.
I'm out of time for now so I have to stop this post here, but there will be more later.