I kind of had to keep my composure after reading this and did not reply to it yesterday. It’s a new day, so hopefully I can put into words on why I feel that this assumption is, for the lack of a better word, terrible.
For me personally, Halo’s multiplayer is based around a couple of key principles. Those are: equal starts, static weapon/item placements (with respawn timers), grenades and complementary map design. Equal start means that every player starts with the same weapon and same grenades. The benefit of this is that no one player is overpowered or given a leg up. Static weapon spawns is for a power weapon (such as sniper, rocket launcher and so on) placements around a map, those respawn after a certain amount of time after the one lying around is picked up. Grenades are kind of the randomizer, you use them to get out of though spots. All those elements are layers of the game and create depth. With equal starts people are more invested in getting the weapons placed around the map, because they want to keep the other team from getting them. It also indirectly promotes map movement (“Who is getting the sniper? We will go get the rocket launcher.”

and team play (“Player x has the rocket launcher, he is camping in the x room!”

. Often those elements influence the map design, because you have to take into account every possible scenario.
With Halo 4’s multiplayer much of those ideals are gone and replaced with a whole new set of principles. There is a loadout system which lets you customize which weapon you spawn with, not only that but you can chose which type of grenades you want and get extra help with the perk system. While playing the game you can earn ordnance drops in which you can call in certain weapons or items. Does that not sound like another popular game? Well, yeah. Chief argument for it is that it puts more power in the hand of the player. All good and all, with good intentions, but that breaks all balance because you have about a thousand possible variations. The clean, everybody is equal approach is much more inviting and practical. The ordnance system is kind of a replacement for static weapons spawn, the problem with it is it removes the element of urgency you had with it – no more effort to keep control of a certain part of a map or even outright confrontation trying to manically to pick up the power weapon first (and doing It again 3 to 4 times during one match). The worst effect these new principles have had on are the maps, they are now backdrops instead of being crucial to the game because well nothing promotes them to be explored or taken advantage of. You might have noticed a pattern there, nothing about this new philosophy is build around longevity – it’s built to make a good first impression and it really does, the shooting is great and feels overall well built. In this day of age, that is all that is needed for games, because people move on from game to game faster these days. I feel like that is a wrong way to approach a game, you should always strive to keep players engaged and coming back.
There has always been a certain learning curve to Halo and that can be intimidating for some people. There are multiple ways to combat this issue though; Halo 3 introduced social playlist where the player gets time to play with a lower pool of players just to get a feel for the game. This is an ideal way, because more experienced players are not handicapped. Halo 4’s approach to this problem is by making the whole game accessible from the start, but never really removes those training wheels. It would have been interesting if they started out “Cod lite” and gradually when the player ranks up the more intricate Halo elements are introduced. Again, another aspect that kind of highlights the short- term thinking instead of the long-term vision. There are so many interesting thing in the Halo design DNA that should be used, but are not even taken advantage of or just completely abandoned for no reason. Now look at some popular e-sports games, like Starcraft, League of Legends and Street Fighter, what do they all have in common? They respect their hardcore DNA and people flock over to play those games. It’s not just about respecting its core fundamentals, it also expects players to play it for a long time. You see this in for example adding ranking, spectator mode and such. Those games give a great, maybe a little intimidating, first impression but also, to hammer this point again, also are built to keep players engaged and entertained. “Pro-gamers” or regulars wanted this is not something that is selfish, they want the game to succeed and get a huge and diverse population for the right reasons – because in the end it benefits all parties. More options? More diversity? Why would anybody want to say no to that.
I agree with a lot of this, but I'm not 100% sold on the idea of prioritizing the needs/desires of the top-end, ultra competitive players above all else.
I DO agree that it's imperative for the developer to understand the central pillars of a gameplay experience, keep them in place, and ensure any evolutions of the formula are complementary or strengthen those pillars, rather than undermining or replacing them.
Full disclosure: I'm not an ultra-competitive, top-end player. I think I'm pretty good. I rank in the low-to-mid 40s in every playlist I played in Halo 2 and Halo 3, and I reached General rank in Reach (can't remember what rank, but it's kind of irrelevant since grades are all credit-based). I do well at Team Slayer, but prefer Objective (4v4) and BTB objective.
My issue might be totally one of misperception, so please educate me if you think I'm wrong, but it seems to me that the top 1% of Halo players have an overriding obsession with the notion of purity. This not only makes them resistant to ANY kind of change, it also frequent comes at odds with what I love about Halo games, combat variety and emergent gameplay. It seems to me the prevailing idea of the ideal Halo experience to the top 1% of competitive players is two players, with the same precision weapon (pistol, BR, DMR, whatever), circle strafing around each other until somebody scores the final headshot.
So as somebody a little more than casual, but not quite competitive, here are the pillars that matter to me, many of which align with yours:
Shoot/Grenade/Melee - Halo's version of the triforce. You mentioned grenades, but I think it goes beyond the simple use of grenades. I think any time the game starts undermining the usefulness and use of grenades and melee, the game suffers for it. Halo 4 is a prime example. The combination of an arsenal that leans heavily toward long-range, combined with a shallower grenade arc and a less-than-awesome melee ensured 99 out of 100 battles came down to mid-range pinging contests. Halo 2, with it's emphasis on dual-wielding, is another example of where the series got away from the thoughtful, strategic and skillful ballet of shooting mixed with grenades to create space and flush opponents where you wanted them to go, and melees, which could be used to punish players that let their guard down in mid-short range battles.
A varied, balanced and USEFUL sandbox - This is where I start to diverge heavily from the super competitive crowd, because I honestly believe weapons like the AR have a place in the sandbox and SHOULD be useful/powerful. EVERY weapon should be useful/powerful under specific circumstance, and disadvantageous under other circumstances. And yet you'll hear the argument that 'it takes more skill to use a precision weapon, therefore a precision weapon should win in every circumstance'. To which I would respond, 'wow you have a fragile ego'. The BR, or DMR or pistol should not be the best option in every single fire-fight, because that will inevitably lead to 90% of fire-fights offering the exact same experience, where the exact same tactics and skill-set come to bear. By comparison, a balanced sandbox where every weapon can be used to great effect under the right circumstance ensures a great variety of combat experiences, where different tactics are put up against each other, different skillsets are put up against each other and smarts/strategy weigh just as heavily as 'I can shoot a dude in the head real good'.
One of the reasons I enjoyed Reach a great deal despite it's flaws was because I haven't played a Halo since the original where I saw a wider variety of weapons getting a ton of use throughout every match. Bloom was imperfect, but it's practical impact of forcing players to choose between range/accuracy/rate of fire helped ensure that there wasn't one default go-to weapon, and that every weapon in that arsenal felt useful depending on your playstyle or situation.
Equal starts - We agree with this, though I think we differ on the meaning. I think equal means balanced, not homogeneous. I honestly don't mind if another player starts with a different weapon or ability than me, so long as the weapon and ability I start with is just as useful and effective. Players in Team Fortress 2, for example, start on equal footing. But they certainly don't start with the exact same weapon and ability loadout. The same can be true for Halo, provided it is balanced and tuned correctly. Thus far, homogeneous starts have worked better, but I think that's a failing of tuning rather than concept. I think giving players custom loadouts and unlockable weapons is a terrible fucking idea, but I don't think letting players choose from a selection of set, balanced options is unworkable. HOWEVER, they need to include a way for the opponent to immediately recognize what 'package' they're dealing with from a distance, whether it's through a modification to each character's silhouette, a color scheme, a fucking icon over their head once they come into view, whatever.
Static weapon placement - Yes. That's really all I got. Remove static weapon placement, you negatively impact movement through the map, you remove different facets of map and gametype strategy that players have to consider on the fly while doing battle with the opposition, you remove the impact of map control and strategy (how many people do we want locking down that weapon, as opposed to charging the objective, as opposed to covering our asses, etc).