Your perfect game

I would like to play something similar to old adventures/platformer games like Rachet and Clank, Sly Cooper, I miss those games...

an ARPG like diablo 2/torchlight
no fancy shining spell, but need enough SFX to get enough OOMPH for each hit

basically just make a game with perfect SFX for hitting/defending/spell, preferably also great soundtrack. make gamer feel satisfied killing even 1 enemy (not too hardcore like dark soul though)
end game content/NG+ is a must
satisfying combat, story no need to be fancy but just enough to know what are you doing and resolve it
also no need for fancy visual which bog down PC (there's modder to do that)

if you know Old School Freelancer game. That's my Perfect games for me!

Crusader Kings + Total War + Mount & Blade = Me never leaving the house again.

An immersive sim, like Prey or Deus Ex.

Dishonored 1. Haven't played the newer games yet.

Everyone has different taste so you can not satisfy all but if it has some unique idea then it is higher chances that peoples can accept it and also risk of reject it. More risk more gain or loss.

Evoland & Evoland 2 :D

I love story/lore-rich games, for me, the story makes the game. The best kind of game for me is an immersive game where the player's decisions shape the story and the world of the game.
My top favorite games are Dragon Age, Mass Effect, and Skyrim.

I play a mix of grand strategy, racing, platformers, and simulation games. Among my tops:

Sid Meier's Civilization V
Stellaris
Victoria II
Cities Skylines
Test Drive Unlimited 2
Mario Kart (insert version here)
Super Mario Galaxy
Portal (1 & 2)
Super Meat Boy
Universe Sandbox
Robot Wants It All

Hollow Knight

Life, but with quicksaves, balanced multi-player, and no permadeath.

I think some City/world building simulator, where you can come thru ages of your city/world and be part of it?

Fallout 4 without bugs, creation club (credits), bugs, Bethesda as dev/publisher, bugs, and with a better engine.

An immersive A-RPG with Kingdom Hearts 2 style gameplay

A mix of Gothic, Dragon age, Victor Vran and Vampire Masquarade series will probably let me forget about basics of hygiene needs. It would need a great story with many possibilities and character making, so players will love to play it again for try a different combinations. Singlepalayer with co-op option would be perfect for me. Also it would be nice if guest would get changed by rng, so side missions on map will close sometimes or get changed when I do not care about them for a longer time (as example: if I am looking for a murderer in town and do not solve it, he can murder someone else, which will affect other quests. It would also make an atmosphere).

Edit: Also if you are looking for theme, I still haven't found on steam some rpg like VVampire: The Masquarede Bloodlines, but made in werewolf world.

When I was young (like 10 years old) I was thinking/dreaming of what a "perfect" game would be gameplay + graphic wise.
I was playing my Dreamcast back then and there was a game that stuns me because it has strange but also awesome and colorful graphics for a "sport" game : Jet Set Radio.
The graphics style is called cell-shading and I always had the feeling that this style of graphics could work perfectly for many kind of games.

That's why I had the idea of a multiplayer soccer game with cell-shading where every player just control 1 player and you could have 11vs11 games or 10vs10 without GK or less. It could also be some kind of MMO idk, but back in the days I'd just love to play a game like that.
JoyCity almost made a game like this few years ago (Freestyle Football) but they let it die because they couldn't balance and fix the game (it's just a greedy company).
Also Zelda Breath of the wild had this kind of graphics and it works great for RPG/open world, we need more title like this one.

Good luck with your game development.

It would be survival game with a lot of interactive items (food, drinks, clothing). With detailed survival mechanics of cold, thirst, hunger. In perfect scenario map as huge as can be and great story to go along with it. Possibly with different areas where climate changes from winter to summer and in between so you have to pack provisions and find appropriate clothing.
Very close comes Long Dark. But I've been wondering about trying my hand at game development as well and coming up with something I would love myself.

What I specifically dont care for survival games is huge but empty world and no story (as in sandbox mode where you aimlessly wonder). Its good to a point but when I'm pressed for time and have several hours to enjoy a game I much prefer to get a story with that time as well instead of just freeroaming.

I believe that to make a "perfect" game (I don't like using the word perfect because: (I know this is very cliche) nothing is perfect). You, the game developer should also enjoy making the game that you would like to play yourself, because if you don't enjoy making a certain type of game that even though somebody else enjoy, then it wouldn't turn out so good. Thus, I think you should instead look on what your "perfect" game would be first, then here as a second resort. (I am not a game developer so I might be very wrong, so take everything I said with a grain of salt)

RPG , Like Witcher
Open World Red Dead
Fallout 4

Interesting thought experiment, For me personally, I'd say some kind of multiplayer social (so MMO-based) with meaningful and pure time-gated progression (so something RPG-like or inventing entirely new concepts, especially considering the social aspect), with either subscription-based monetization or a highly ethical F2P model (I hate F2P in general because it always turns out to monetize on gameplay concepts, but if you were somehow able to stick to 100% cosmetics or similar, that would be perfect). The gameplay wouldn't have to be innovative or consistently non-repetitive (that's probably unrealistic), but should feel fun to repeat, instead of breaking down to doing standard daily/weekly/monthly whatever grinds for imbalanced rewards like a lot of AAA games do just to force people to regularly play boring content. Finally, new content should be available from time to time, either through post-game content/DLC and/or player integration/modding/addons similar to the Steam Workshop.

Edit: In addition to the game itself, assuming it is heavily multiplayer-based, an additional criteria I'd add is to enforce strict policies on player behaviour to combat the increasing amounts of shittyness that is infesting every corner of the internet. This is another good reason to choose a paid model above F2P, because assholes (and other issues, like bots) are harder to keep out of F2P when they can much more easily continue to simply make new accounts. Ideally, this should involve a serious and trustworthy support system where people will interact with human moderators with access to detailed logs, reasonable response times, and face penalties for fake accusations.

The most important things for me is achivements, shiny chests and exploring. (maybe a nice sound when you open chests like Zelda Ocarina of time!) :D

I always thought the semi-mmo way Fable 3 was, was super interesting. The fact you can "see" other players but cant actually see them. I would've liked another game with this feature.
I honestly miss games like Kingdom of Amular, and kinda wished for something like that to prop up again.

A perfect game would have:
-A leveling (or just a growing stronger) sistem, with customization and variety. Various combo abilities, no restriction based on class or whatever but just on where you spend into. This allows you to have satisfaction and make the experience personal.
-Every combat must feel like it can be done multiple ways, everything can be interacted with, like in the Divinity Original Sin series. Use your brain, or just use something broken, or both, or neither.
-Action, but not too action. You can jump, run, swing your sword or whatever, but you can't just button smash trought everything. Games like bayonetta and DMC are an example, they are fun but that wouldn't work with the previous sistem of combat. Think and fight.
-Huge world, various places to visit. Remember Skyrim? No I mean what it was in the developers mind, not the result. Yeah that. A world in which there's always something to do, nothing is repetitive, maybe a real world and not a map, if you go straight in line you would end up at the start of the journey. Maybe it's excessive uh? But what if...
-Your progression is linear, with some stops by. You know where to go even if you can go everywhere, because either the story let's you understand that or the game will just kill you. You can still do whatever in the places you should be, secondary quests, or whatever, but you know you should be there.
-Some choices matter, really matters, and you have time to think about it. You know like in The Witcher series, in which you have to decide something, but you have the time to see for yourself what's really all about (like the villagers fate). I hate those choices in which you have to decide istantly between A or B without really knowing much, it's your decision not a random throw. And that brings us to...
-A third option. Old Obsidian really did this very well, it seems like you have only two choices, but the game let's you do something else, because the world is not black or white. Makes you feel in control.
-Characters must feel real. The story must feel real. The interactions must feel real. No random generated people or enemies.
-No politics or whatever. In old games the game showed you some sort of ideology, but it never rewarded you for following it, or pushed it for it. Some times the "bad choices" led you to a good outcome but at what price? In most modern games, you just have to follow a choice because it's the one that gives you the most stuff or whatever, while making it seems like you have a free will. Looking at you Outer Worlds.
-Optional RNG. You have to feel like your victory or lost is your fault.
-Maybe costant saving like the soul series? IDK
-I got tired of writing stuff so I will stop lol
This is a game that will not exist because of the amount of stuff it has but that's just for now, in the future maybe