After sinking over 100+ hours into the game and going through the initial learning curves and began to get into the meat of the game, only then do you start to see the glaring issues which seems to have a fairly bad case of identity crisis, because it doesn't know if its a single player game, or a hardcore grindy MMO - this will review will contain some minor spoilers.
Crafting is a huge problem because simply put, too many items each with their own stats/tier so your base usually ends up with 50 different chests each with their own items just so you can try to sort out the mess of items when crafting, which often takes up a huge chunk of your time just trying to find the individual peices you might need, and later crafting often requires multiple items to make parts of an item, which is then a part of the final item and crafting becomes tedious and slow, smelting ingots for instance can easily take 30 minutes to an hour for prime example, you cannot even see what attributes the item needs before you have even crafted the basic materials so often requires looking at online guides just to get a basic idea, terrible idea really.
Lack of weapons, instead of adding in a variety of weapons like most games. This game decided that your tools are your main weapons, and because of that you end up with countless hours of using the same tools to defend yourself such as wood cutting axes or mining pick axes, eventually you can craft firearms eventually but that leads to the actual combat which is a mess and opted for forcing the player to fight large groups of bound enemies, sometimes so many it affects performance or large bosses which have broken, cheap mechanics often forcing the player to use equally cheap tactics to win, some enemies are so broken by moving at such high speeds often very difficult to attack them, and can change direction at high speeds in an almost comical way.
Combat is further made frustrating by the sheer lack of empathy from the developers towards the players, these come in the form of debuffs, naturally when your cold, hungry or wet etc, however these debuffs are so harsh such as literally halfing your HP, or removing huge chunks of your stamina pool that it becomes more annoying to manage your debuffs near constantly, having to cook good food is once again, annoying and poorly throught out as it requires too many materials, so often the player will just resort to basic cooked meat and berries for stamina, sure you can make better meals but the time invested is significant.
Stamina is a huge issue early game because everything you do requires a stamina cost, in the opening first few hours you can't even climb rocks efficiently and can basically climb a few feet before your stamina runs out and you fall back down, which is a huge problem for some puzzles which require climbing, I'll get to the horrible puzzle design shortly, but because stamina is such a focal point for everything including combat, anything that restricts your stamina such as being wet is a huge problem, often during rainy weather you absolutely must use an umbrella which takes up one of your hands so if immediately get restricted to what tools you can use, since the 2H weapons do the most damage, you will be restricted to either knifes or pistols if you have unlocked them, and since stamina doesn't regenerate that quickly, in combat without the ability to attack or even sprint you are at a huge disadvantage.
Puzzle design is heavily flawed, there are three types of puzzles in Nightingale, and two of them range from being extremely annoying to just broken, the first one is flipping switches in order however they are almost always out of sight, behind walls or simply hidden and can range from 3 to even 6+ switches, naturally the more switches you need to push the harder and more time consuming it becomes, sometimes even finding a switch becomes an exercise in patience before sheer frustration comes in, and the kicker? These peoples will just often yield 10 to 15 essence, yes you heard me correctly. The second type of puzzle involves finding glowing switches and pressing them, the order doesn't matter but some are only exposed when killing fast moving wisps which patrol the area, I've found this puzzle to be actually the most annoying and broken, often spending 10+ minutes trying to find a particular switch and ending up giving up because it was either not present or bugged with the final puzzle being your stereotypical jumping puzzle which is the easiest of the three but again, you are being rewarded with breadcrumbs for your efforts here.
Even building has significant limits, you can only build a base with a maximum part limit of 300 or so, with a strict structure limit on 100 on your home realm, which is basically your own private realm which you can invite friends if you wanted to make a clan realm for instance, however that being said...the more structures on your realm the longer it takes to load. Later structure parts especially for the nicer looking parts require significant time investment to craft once again so whilst you could make a nice looking base, be prepared to spend days if not weeks doing so especially for higher tiered buildings such as the pagoda set for example which requires multiple crafting and multiple subcrafting parts which takes time, I'll be honest here the only good element for building bases is the fact you can lay out your base in advance and supply materials at anytime.
[Minor Spoilers]
GRINDFEST warning!!, later once you have progressed though the story and unlocked "The Watch" after you have finished the bulk of the lazy quest design which is talk to some people, do typical quests for them so they point you in the right direction whilst slowly upgrading your tools, the problem with the Watch is this point the game becomes an MMO, the watch is the hub for this mode which then forces you into absolutely garbage level grinding for many recipes, some of the better ones costing 1,100 T3 essence, by comparison you could perhaps farm a few hundred T3 essence clearing one ENTIRE ascended realm which can take a good amount of time, or perhaps try your luck at getting into a party for a vault run which yields just slightly better essence rewards and chest drops which are not shared and people steal the loot all the time, heck people sometimes just join runs PURELY to steal the drops, or AFK leech.
Even upgrading your items requires essence farming, basically everything you'll be doing in Nighingale is some form of farming, and essence farming is main focused grindfest since everything revolves around it, even repairing your items requires essence and once you get higher and higher tiers it becomes very tedious especially considering the lack of progression for your character which happens in large immediate jumps once you've unlocked better equipment or higher tier upgrade tables, and upgrading your equipment form common to uncommon through to epic, yes you guessed it....haha....requires even more essence, arn't you glad? Unfortunately the over reliance on essence grinding is perhaps Nightingales greatest failures, even if all the values were slashed and the amount of essence rewards increased, it'd still be somewhat of a mindless grind.