I'm gonna take this to mean 'What does your ideal Gaming Industry look like?'
I can't speak for every game because there's some genres I just don't play, like MOBAs, Fighting Games, RPGs. So, I won't talk about them because my idea of 'Peak MOBA Gameplay' would just not be as developed as FPS games, so I'll leave them alone.
I also know this won't be for everyone, but the question isn't intended to be unbiased, so I won't be unbiased.
(Unless it is, in which case, uh... Ask again?)

So, first of all, I want most FPS games to have singlefire weapons to take the focus once again, and let automatic weapons like SMGs fall to the wayside as secondary weapons to finish off opponents.
Make things like shotguns, revolvers, explosive launchers, or crossbows the center of most game's design and let SMGs or other automatic weapons be secondaries.
I think the very committal design of singlefire weapons makes them far more entertaining to use and fight, both in singleplayer and PVP games. For some weapons, like Snipers, you either hit the guy, or you don't.
Even less committal ones like Shotguns and Rocket Launchers, you can hit partial shots by connecting a few pellets, or hitting some splash damage.
Allowing them to be the primary form of damage also means you don't need to follow the design of making shotguns insanely lethal regardless of accuracy up close like they are in COD. You can let Shotguns be very precise weapons like they are in TF2 and Splatoon because they won't have to contend with Automatics that can laser them from miles away.
Even in TLOU and RDR, I think almost every weapon in the game being singlefire makes these games far more entertaining to play, and I think that alone makes these guns the best of R*'s catalogue.

Secondly, more interesting unlock able weapons.
Most custom weapons in games are really samey. "This gun has a slightly faster fire rate, but a liittle less damage."
"This gun deals slightly more damage, but is a little bit slower."
"This gun has a higher clip size, but reloads slower."
I'm not saying these basic stat swaps are bad, or that they can't change how you play the game. The relationship between Splat Charger and E-Liter in Splatoon shows this, as Splat Charger can afford to be more aggressive than E-Liter can, and at times, may even have to. Exclusively because it has less range, but shoots faster.
But, when that's the only thing your game has, the playstyles just don't have enough variation. TF2 would be far less interesting without strange and unique weapons like the Eureka Effect, the Beggars Bazooka, The Winger, The Kritzkreig.
Or, in Splatoon's case, the Squiffer, Explosher, Tetra Dualies.
In short, I just want developers to get more creative with their weapon ideas. The most fun I had with Fortnite was with unique mobility items like the Hammers, since they allowed you to be really aggressive. Though, unfortunately, due to the nature of Battle Royales, a lot of people don't use them that way.

Third, this one goes for the singleplayer shooters, I want better AI, both for the enemies and for allies.
I was playing Selaco, and enemies are constantly doing something, they always counter whatever it is that you're currently doing.
They'll spread out if you're using grenades, start hiding if you're sniping, play defensively if you're using a shotgun, try to flank you and bomb you if you're stationary.
It really forces you to use everything, think constantly, and really engages you.
Then, if you compare that to some COD games where they just sorta sit around waiting for you to shoot them, or HL2's AI which - other than a few quirks like always having at least one guy shoot, but not everyone - kinda just walk at you. Or even Splatoon's Singleplayer AI which barely even knows how to move, it's REALLY boring and uninteresting, which I think is the worst crime a game can commit.
Though, I've got a lot to say about Splatoon Singleplayer games.

Fourth is that I want mod support to come back, both for SP and MP games.
For SP games, it's literally a net benefit from the player's side. I'm fairly confident Minecraft's playerbase would drop dramatically if you could no longer mod it. Half-Life wouldn't still be relevant if you couldn't mod it. Hell, most of VALVe's catalogue wouldn't exist.
And on the MP side, just having client side mods like hit sounds or HUDs just lets you have an added level of personalization, which is something I really value in my games.
I'd also just like to change some Splatoon paint colors. I've seen some really pretty looking ones I'd love to play it, but Nintendo be Nintendo :(
Someone once asked me, 'Well, who decides what mods get to be played?'
That's a stupid fucking question, half of them are client side customization. Even the server side ones like weapon changes, custom weapons, or custom maps would just be run on community servers, they don't have to be added to the base game.
I do know this would take some work to keep people from practically using cheats, for example, mods that increase the volume of Spy's decloak, or the size/length of muzzle flashes, but I think the work it'd take to limit certain things is worth the amount of freedom people can have with their games, especially with live service games that get constant support.
Besides, singleplayer devs don't get that excuse.

Fifth, I don't want to get rid of microtransactions or live service. I do think it's fun to have your favorite game get constantly updated, I also think it'd be really lame for some games to come out and never get updated again. Splatoon sure would've been less fun, and so would TF2.
(Unless it's Fortnite where you're basically playing a new game every update. That's... Actually kinda annoying.)
Microtransactions also allow these developers to deliver that support. You can't work on TF2 for 10 years for free, and you do need some way to get new players.
My problem is when it gets predatory, or anti consumer, which I know is The Pipeline, but I do feel like if there were just... Laws, it wouldn't be as big of a problem. Unfortunately, that's so much easier said than done.
So, I just want this stuff to be less predatory. Let people buy the fuckin' battlepasses and do them whenever, instead of just in this 2 month period. Rivals skins do not fuckin' warrant being 20. FUCKING. DOLLARS.
I AM NOT JOKING, TO BUY THIS FUCKIN' BLACK WIDOW SKIN I WANTED, THAT SHIT WAS THE SAME PRICE I BOUGHT RDR2 AT. RED DEAD REDEMPTION 2 WAS THE SAME PRICE AS THIS FUCKIN' SKIN BRO. IT AIN'T EVEN LIKE RIVALS HAS A TRADING ECONOMY, WHERE SOME ITEMS ARE RARER THAN OTHERS, IT JUST MAKES HER SUIT WHITE BRO. DATS IT.

Also, crunch time is gone. I don't have to explain myself, it is just vaporized. Give devs the time to make their shit pls thx
Also, I want more coop games. I don't actually have anything to say about it, I just want more coop FPS games. Make more Army of Two games, pls thx.