Question is, how many of those problems are objective and subjective.
I mean it is my opinion, and my tastes might be different from other people, but here are my main issues with the game. there is a lot of smaller stuff but I don't have all day.
1) The progression in this game is completely quantitative. Numbers go up (i.e. attacks do more damage, or your town is better at treating stress and disease etc) and down, but beyond level 1 (which can be achieved by completing one apprentice mission with a fresh recruit, there are no new qualitative changes to the gameplay, meaning that the way you play stays the same once you have access to the full customization of each character, and this happens very early on. Trinkets help a little in this regard because they also just change the numbers.
2) there is no overall tension or urgency in the game's overall objective (i.e. restoring your ancestral manor). The game does provide tension through the RNG in the dungeon, however, and it does this quite well. People complaining about the RNG and how it is not fun are wrong, as it is one of the sole sources of fun in this game. The game hands a shit situation on a regular basis, and it is up to you to solve the problem of how to survive.
The main issue with this is that failing has little consequence beyond the time and resources you invested in each hero. The Dungeon isn't going to win or put you into a fail-state if you don't beat all the bosses or do the caretaker objectives in time. You can take all the time you want, which means that you never have to send a hero in if he has high stress, and you can always use fresh recruits (who are free) to raise money to keep your A-team fresh. In practice even this is usually unecessary, and you just develop a B-team that eventually becomes quite good as well. So essentially all the resources that the dungeon generates (money and heirlooms) are infinite resources that you can generate at no cost (since fresh recruits are free) except for your time.
3) most of the quirks are meaningless. Your characters acquire all these little quirks that are supposed to give them personality, but most of them don't do much and even the worse ones can easily be negated by spending time in the sanitarium (which just costs money, which is an infinite resource).
No offense, but your post made it pretty clear to me that you're not the best person to listen to when it comes to opinions about game balance in Darkest Dungeon. You sound like you might be deep into the game mechanics in a way that most players probably won't ever be.
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I'm not criticizing the game's balance. I think the changes Red Hook have made are actually good, and the game's issues are deeper rooted than these balance tweaks like corpses and heart attacks.