Thanks for the reply, you raise some very interesting points about the game, some of which I would like to argue against in this reply.
In the first section, your problem seems to be that the platforming sections are too hard for the movement system of Hollow Knight. Personally and from many others on forums, I think that the movement system is very precise compared to most games: almost every move is executed on the button press, there is no momentum (or 'float', granted the jumps aren't super-quick) and you have full air control at all times. Sure, it can be fiddly and hard to master, but since you said you beat Traitor Lord without losing much health (I assume), you should be pretty familiar with the controls by now. Have you done the white palace or path of pain? I don't think you did, but me and many others find these platforming areas to be very challenging, but definitely enjoyable and fair. However, not all movement systems are for everyone and I see how you can get frustrated by a platforming section (as I said in the article, I had to cheat a few times to skip past these when I did not yet have hiveblood).
You conclude with the claim that the game is too hard for the casual controls. I understand this is your opinion, but in my belief, most others tend to think the opposite. With a quick search I found these on popular review sites:
'fantastic controls' https://kotaku.com/hollow-knight-the-kotaku-review-1827367425
'precise control' https://www.youtube.com/watch?v=7t1mxoMIDfY 11:43
'pitch perfect controls' https://www.technobuffalo.com/reviews/hollow-knight-review/
In the bosses section, you compare the bosses to a boss you say is' built around taking down his shield while avoiding attacks until you put him in a vulnerable state and have a couple of seconds to hit him before he shields again'. Further on, you mostly talk about iframes, rng, projectiles etc. and do not elaborate on the subject. Unless you specify, I cannot really agree with this: except for Uumuu, who I agree is a bad boss, you can hit them at any time in a great risk-reward system. The stunned states are just a breather and a chance to heal or do extra damage.
Your main wish is to have a counter/parry/block system in the game. In my opinion, that would ruin the game entirely. I think you are comparing the game too much to melee combat games like Dark Souls that have block-hit type gameplay with less focus on dynamic or vertical movement. I would compare Hollow Knight to a radically different game to suit my explanation. Mario is a mostly a game about dodging projectiles and getting close to enemies to kill them. Now imagine a Bowser boss fight where you could parry his fireballs or had a roll with iframes to dodge through them. It would no longer be a fun dodging game and an exciting ascent in difficulty as you get closer and you have less time to react to his attacks. It would be a simple 'press the button at the right time' game, much less exciting than the original one. In conclusion, the boss fights in hollow knight are more of a platforming game type challenge with the added risk-reward element of having to go close and expose yourself to deal damage.
As a side note, you can use desolate dive to get a generous amount of iframes and deal damage if you have the soul. Furthermore, there is actually already a parry system in the game: you can parry sharp attacks with the right timing, though it is incredibly hard to pull off and not worth it.
While the healing system has its problems, such as being near useless in harder boss battles, I think having a permanent Bladur shell is definitely not a good idea. It takes away the risk element and deincentivizes good timing. You could just spam the button to not get hit and heal as much as you wanted. Sharp shadow is a unique playstyle that focuses on dashing through enemies - this is perfect for a charm but a strange addition as a normal ability. Thorns of agony is just bonus damage for making a mistake, I don't see why that should be a regular ability. As for the range increase, I would love that, but not sure if it would be balanced or not.
In conclusion, I think your main problem with the game is that the controls feel unfair when compared to the challenges. As a person who started this game as an incompetent player, I can assure you that if you spend time learning the controls, the game becomes just as rewarding and 'tough but fair' as the other games you mentioned. If you really feel that the game doesn't suit you, I respect your opinion, but I believe for most of us the combat and platforming systems are great as they are and do not need most of the changes you mentioned.