This is a follow up forum to my previous post to better explain what I think 343 did wrong in Halo 5 and give examples of what is wrong as well as areas from previous Halos they should draw ideas from. With Halo 5 though there were a LOT of mistakes, I just want to help 343 make it the system seller/killer app that it is very much capable of being! A lot of these are personal opinions so feel free to disagree but please give good reasoning as to why 
The BAD:
-Very LINEAR mission design
I think of missions such as Silent Cartographer, Attack on the Control Room, Tsavo Highway, The Ark, and The Covenant as missions that were very non-linear. Yes you still have to get from point A to point B but there were many different ways to achieve that. Halo 5 feels claustrophobic in comparison. Previous Halos had a very organic way of merging ground and vehicle combat.
-NO epic scale battles
The Ark and The Covenant in Halo 3 are the definition of Epic Scale Battles on console. To this day They are still amongst my favorite levels ever designed in a game.
-Where Are the SCARABS??
The Kraken is just a platform of enemies that does not actually attack you and the Kraken itself does not move whatsoever. Even in Halo 2 where the scarab did not attack you directly you saw its capability to destroy everything firsthand. Halo 3 the scarabs were actual enemies that would attack and engage the player and also had enemies on them. The scarabs are a staple of Halo 3 and my favorite enemy in any game, please bring them back. Maybe even drive one 
-Even Vehicle missions are just larger hallways
I know some levels in Halo 5 are a bit more open such as Meridian but even those levels still did not feel as open as levels from Previous Halos. That level in particular was a very ugly level graphically and also all we fought was Prometheans 
-Prometheans still not fun to fight (Soldiers are very annoying)
The knights and watchers have been greatly improved but the soldiers are nothing but a nuisance since they teleport all the time. I think to make the Prometheans a more interesting faction since they are here to stay is to: make the soldiers not teleport (act more like elites), have Promethean vehicles equivalent to the warthog and scorpion, and have more ranks in the units that can be identified visually (for instance have white, silver, black, and red unit colors)
-ZERO characterization (little)
As someone that only played the games and read The Fall of Reach (a very long time ago) I did not know what was going on for a large part and did not know the large cast of characters. I only knew blue team a little from the book all those years ago. When writing the game assume the general player has not read all of the EU and lore. I was very lost and did not care about any of the characters, especially Vale and Tanaka. Next Halo use a lot more cutscenes to properly introduce characters and give an intro video that catches players up.
-Killing off Jul MāDama for no reason
While I did not enjoy playing spartan ops I very much enjoyed the cutscenes and story of it. Jul MāDama was built up as a very strong character with lots of personality and motivation. Halo 5 erased all of the events of Halo 4 and Spartan Ops for no reason and they killed off Jul to show Locke as a powerful character. Instead it just made me hate Locke more, should have just arrested Jul as him meeting Arbiter could have been a very interesting story arc.
-Terrible story, too few blue team missions
Same as before, the story IMO was an abomination to the halo franchise. I needed more Blue team missions for more context as well as getting to know Blue team. I did not get to know blue team and did not get to see what all they were always up to. Where was their Meridian mission??
-Halsey wanting revenge to not caring anymore
In Spartan ops Halsey wanted revenge on ONI for taking her arm, now she does not care, even to Spartan Palmer who shot her. Why does Spartan Palmer not like Halsey again?
-Focused too much on coop yet NO SPLIT SCREEN?!?
No split-screen is a shot in the face to all halo fans. Halo is known for splitscreen and LAN parties. Playing campaign on Legendary IS HALO. Making it to where there always has to be four Spartans, even in AI form is detrimental to mission design. It ruins the ability for stealth missions and does not allow for the quiet moments or feeling of solace that previous halos allowed. Even Reach had some parts that allowed this and I did not like Reachās story at all compared to the book.
-Content Held Back
No proof of this, but it seems like a lot of content, especially content seen in pre-release trailers, was ready for the game but to keep people engaged longer they thought it was a good idea to release it throughout the next year. I love that itās all free but i wish for more maps, I do not like much of the map design.
-Too much focus on 60fps, graphics are good but not great, same with textures
Look at the game, the textures, particle effects, shadows, resolution, amount of AI, and etc were all downgraded to always lock at 60fps. I prefer 30fps if it would allow the game to include everything they had to downgrade. For players that want 60fps allow us to toggle graphics options for the campaign at least.
-Too Short of a campaign
Self explanatory, can be beaten in 4 hours. Yes it takes longer on Legendary but I did not even care to play it on legendary because of how poor the story and level design was.
-Not enough Playlist at launch
I still do not think there is enough playlist. Needs 4x as many permanent social playlist and an alternative warzone that is more casual. Not all modes need to be super competitive
-No Elites in MP
Please bring back invasion
Great game mode and good reason fro having elites in MP. Make it a next gen invasion where its like 32 v 32. Battlefield can do it and look very pretty, why can Halo not?
-Map rotation is horribly broken
The map rotation is atrocious. Please allow a veto system as well as staying in a lobby. Also fix the UI especially for lobbies so its easier to see everyoneās rank and gamer tag. Look at Halo 3 or Halo 2 or Reach for a much better and cleaner UI.
-No armor unlocks for progression and skull collecting
I want armor for finding every collectible and beating the game on legendary. I want armor for achievements and armor for ranking up as well as the ability to customize all parts. I do not like armor sets. Why has the series taken away so much from this aspect?
-No Campaign Theater and no Forge at Launch
Iām glad we got forge flawlessly and improved as well, but we should still have had it at launch. Please add AI to forge as well so we can make our own engagements and mini-missions
Also I loved reliving moments from the campaign in theater mode, why is this gone?
-Too much focus on esports community rather then the general audience which are casual players
Halo 5 MP is awesome, do not get me wrong. I love it overall, I just personally suck at it. Needs more modes to appeal to casuals and include different version of warzone. Maybe have the current one, a 32 v 32 PvP only one, and a 12 v 12 one where there is 4x as many AIs so even players who suck can feel as if they are helping their team. 
HALO 5 is a good game, great value. However, it is the WORST āhalo gameā in my opinion. 343 only needs to look to the past and incorporate some of what I have listed to really make a fantastic game. I know you are capable of it 343! I want Halo to rise to king of FPS once again.