Your top 3 downsides of POE

Okay.

1. Too much clicking
2. Too much clicking
3. Too much clicking
...
n. Too much clicking

1. Terrible performance and clunky gameplay.
2. Too much clutter and bloat.
3. Too complicated and requires more studying than playing.

1. Too many useless/boring Unique Items.
2. Have to use 3rd party programs to make game better.
3. Bloated loot, too many affixes, adding even more RNG to loot.

1: Trade
2: Challenges - Situational Challenges are horrible.
3: Having to Re-play the story in a league to have a new Class/Character

1) game performance /cant get if i need new pc or game just runs worse in each new league without info of changes to machine power/
2) melee range sux /unwanted forward moving to perform an attack because i click to dash forward while also press skill button in half second i see a mob on my screen and if that mob is where i dash to...got hit more than wanted cuz i lose time to stop the attack move and dash again to attack in range faster or slam the ground so aoe kill the mob, or i am noob but that sux imo and pressing extra button isnt what i wanna do, QQ xD/
3) grinding every 3 months is annoying already /prefer longer league so i can make a break and come back with another toon but also have plenty of time to enjoy it, else im damn lazy in start of league and play even less effective, eh/

"

I don't want the game to be too easy. Most of my points are quality of life.

And here is your list of stuff that... well... makes the game too easy ;-)

"

2. Bring back deterministic crafting. 3.11 Harvest was a good start.
7. No immunities on monsters. [Expedition]
8. Remove physical/elemental reflect from the map pool.
13. Simplify Heist
14. Make talismans well-rolled again.

Out of the 16 points a whopping 31% of your wall of demands adresses things that directly make the game easier. Technically you are right, "most" of your points don´t focus on that. But given the fact that this thread asked for your 3 biggest downsides and you managed to cramp up 5 in there that directly challenges the level of difficulty I´d still say you are horribly overwhelmed by the game and need it back to mickeymouse in wonderland level.

"

Your other two points are completely useless. They don't add any solutions, don't add anything to the discussion how the game should be heading.
(Ofcourse GGG should introduce new cool endgame bosses with fun mechanics... Wow Einstein!)

And to that comment - First of all, the Thread was asking for my personal view on the biggest downsides. It did not ask for me to give my thoughts on options to improve upon it. So there´s that first of all.
Secondly, giving feedback is already useful as GGG can make up their own mind how they want to adress problems that are brought up by the community. And third: I specifically explained what is crucial for me to enjoy a boss-fight. It is not the drops, it is not the speed of how fast I can kill him or how deadly he is (well, kind of - without risk there is no sense of accomplishment), it is the mechanic skill that is needed to beat him. So yeah, I am pretty sure I made a very valid point what kind of bosses I want to see. Just because you can´t understand that as it surpasses your "give me everything free and easy plzz"-mindset does not mean its not a valid point.

1) too much zoomed in (which leads to lots of offscreening and mobs that slowly creep in)
2) bad performance when lots of stuff is happening (requirements need to be updated)
3) RSI

My downsides in no particular order:

Lack of a death/combat log (WTF killed me?)
On-screen clutter during fights (Can't see what I'm doing sometimes)
Being killed by something off-screen.

1. Melee
2. Visual Clutter (this game needs to come with a seizure warning at this point)
3. Other games have simple QoL things that GGG won't budge on (auto sort stash and inventory? Grim Dawn has that. Auto combine shards of orbs with the push of a button? Grim Dawn has that. Loot Filter built into the UI? Grim Dawn has that. etc. etc.)

1. Generally held back by insistence on balancing around trade economics.
2. Interesting side encounters (past league content) tend to scale up in difficulty too quickly once in maps. Large packs of monsters (usually with a speed aura in there somewhere), especially in some "here, fight in this circle" type encounters, reduces the game to mindless fire/blink/fire/blink reaction.
3. Random "crafting" of sockets/links/colours drastically slows down the enjoyable progression of skill/support choice past four-link items, and makes finding new items drastically less common an event.
4. Interesting mechanics usually added to uniques rather than skill trees.