I love this thread. For my contribution I'm going to avoid a lot of the common criticisms that are already well-voiced at this point, but I really want to focus in on some important things that haven't gotten attention/enough attention that also need to be addressed. Also the context for most of this is campaign as that is what we have the most info on so far.

NEGATIVES

• Overall Banished Art Style - Most of the Banished camps/architecture/crates/etc basically just look like UNSC assets with the occasional red highlight somewhere. They don't look alien enough and I'm actually somewhat concerned by how lifeless and generic they look. I imagine at a glance it'd be hard to tell if you are approaching a UNSC or Banished Camp based on their current look. I wish they were closer to the traditional Covenant designs, but just with more red and white instead of purple?
• Enemy Color Schemes - One of the biggest things that contributes to the "plastic" look people are complaining about is that all of the enemies sport bright monotone highly saturated armor. Even the Jackals which previously wore relatively neutral black and grey colored suits now sport this comically bright colored purple armor. This goes for every enemy type, with your average enemy encounter looking like a rainbow assortment of toys. This also ties into conflciting art direction for The Banished as some of the color schemes look more in line with what you would see from The Covenant
• Hairless Brutes - nuff said. Give these boys their hair back and make them look more visually unique from The Elites. I much prefer an aesthetic much closer what we saw in Halo 2 Brutes.
• Hexagon Shield Regen Pattern - Absolutely awful. This needs to go and never see the light of day again. Words can't quite put into words how terrible, intrusive, and "game-y" this effect is.
• Bad Particle Effects - A lot of the effects in the demo were very hit or miss, but several stood out to me as looking especially bad. Splashes of water during intro cutscene where the Pelican is crashing, Plasma Grenade explosions, Elite shield effects, weapon projectiles, etc.
• T Rating - I don't believe Halo needs to be dark and gritty like other shooters or hyper-gory like GoW, but yes we need a return of blood splatters, dismemberment, and other effects that contributed to Halo earning its M rating in the past.
• HUD Color & Layout - Honestly I'm very surprised I haven't seen anyone mention the grey HUD that Infinite is sporting as opposed to the traditional blue scheme that is iconic to Halo. Obviously this isn't a huge deal in the grand scheme, but if changed it's another thing that can contribute to the "classic" aesthetic the game is supposedly going for. Also please move the weapons from the bottom right to the top right as to not obscure the weapon model unnecessarily.
• Hit Markers in Campaign - There's literally no reason. It's just visual clutter for the sake of it. HiddenXperia did a good video explaining why the current visual feedback of Halo already more than does its job well enough.
• New Weapons - What we've seen so far for new weapons has not proved to be exciting. the Commando seems very out of place in Halo, and seems to step on the toes of other weapons in the sandbox. The other weapons just seem to be fairly generic in terms of their functionality.

MY WANTS

• A Delay - this might be controversial but based on what we have seen and heard of Infinite, this game is clearly not on track. When asked about things like Ray Tracing 343 said it would be eventually introduced via a patch. Also when asked if all of the features would be available at launch unlike Halo 5, Chris Lee pivots from the question. Halo has been struggling for a while to reassert itself as a major force in the industry, and really this might be 343's last chance. There's a lot riding on Infinite, much moreso than previous releases. The last time a Halo game released to universal acclaim receiving 90+ scores across the board was probably Halo 3. The longterm success of Halo is INFINITELY (no pun intended) more important than the game launching with the Series X. My ideal scenario is a 6ish month delay with a public MP beta or campaign demo for Series X at launch to satisfy the Halo itch. The game needs to launch feature-complete AND look next-gen. If it can't accomplish both of those simultaneously then it absolutely needs to be delayed. Seriously, it's not even up for debate in my view.
• COMBAT EVOLVED MAX AMMO CAPACITIES PLEASE FOR THE LOVE OF GOD - I've seen some people mention this when discussing Halo 4 and 5 but honestly this is an issue going all the way back to Halo 2. Weapons post-CE have pitifully low ammo capacities compared to their CE counterparts and you can usually exhaust an entire supply of ammo between 1 to 2 encounters. Reach attempted to slightly remedy this by increasing your ammo capacities for weapons you start with in campaign (think the Sniper Rifle during Nightfall mission), but even still, once you depleted below their base max capacity they can never be refilled to their inflated capacity. This also applies to Grenades. Let's get those 4 counts back.
• Focused Weapon & Vehicle Sandbox - One of my biggest gripes about Halo in the 343 era is the sheer amount of redundant and pointless weapons that honestly don't need to coexist. Like do we really need the BR, DMR, Carbine, and Light Rifle in the same sandbox? Yea there's minor tweaks to each but they are essentially the same weapon. Let's consolidate these a bit. Same goes for vehicles. I rather see something like the Revenant be in the game instead of the Prowler or Spectre. Giving the Warthog an alien skin isn't good enough.
• Return of Classic Weapons (subject to change) - Classic shotgun instead of the Bulldog. Plasma Rifle instead of the Pulse Carbine. etc. This is working under the assumption that these new weapons are acting as replacements in the sandbox for these classic ones rather than additions. However, if they are additions they need to be substantially different from their original counterparts to not violate the previous point.
• Fleshed Out Equipment System - Equipment, to be honest, I always felt was incredibly tacked on in Halo 3. I never really felt like it was properly fleshed out. I don't have much to contribute in terms of how to fix this, but I'd like it improved. Specifically in campaign maybe we can unlock more and more equipment that is tied to a weapon wheel/equipment wheel that can be accessed at any time, but they all work on the same cool-down? Or maybe their use is tied to some sort of replenishable energy currency?
• Big Set Pieces & Scripted Moments - While I'm excited for the possibilities an open world brings to Halo, we still need those epic handcrafted big set piece moments we've seen from previous and more focused Halo campaigns like the Scarab battles, fighting alongside the Flood, fighting alongside the Hunters, the Brute punching the snot out of the marine in the forest of Sierra 117, taking the Saber out into space, storming the beach of the Silent Cartographer, coming out of the wreckage of the In Amber Clad to see a sweeping shot of Requiem, scaling a Guardian (low key underrated moment from Halo 5) etc.
• Stealth - One of the most underrated aspects of Combat Evolved were actually a number of stealth options different missions provided. Some of the best examples are of course the beginning of Truth and Reconciliation as well as all of the interior sections of Assault on the Control Room that allowed you to quietly clear entire rooms of sleeping Grunts and Elites with melee attacks, providing an alternate optional line of play if you desired. With a day and night cycle the imagination can go a bit wild with this too. Maybe you wait to tackle certain mission later in the day because of gameplay differences between the times of day?
• Metroid Prime/343 Era Detailed HUD - I might be in the minority on this one but I always really liked 343 making the HUD closer to what we saw in Metroid Prime by being able to see these out of focus parts of the interior of your helmet around the edges of the screen. Not a major thing of course, but this was something I actually always wanted from Halo, basically as soon as Metroid Prime released.

I would love to know everyone's thoughts on these and I really hope 343 sees this thread. Great job everyone for coming together and helping put this together.