Reading this I was quite shocked at some of your points. I'll list my response per paragraph:
-By far the most discussed point is Sprint, and I expected to see someone yet again opt to remove to feature and I was getting ready to make a disappointes sigh. But when I saw that you actually thought that Sprint was better with schield recharge my brows went all the way up my forehead. While I could understand the point people went on and on about in Halo 4, Sprint being a cheap getaway, I see no real reason why Halo 5 is doing it wrong. Yes you can still get away but you'll sacrifice your shield recharging in the meantime. This seemed like a fair inbeteween for Sprint to compensate for both sides of the discussion.
-I feel like you're overexaggerating a bit when it comes to the "power slam". In no possible way is it a feature that gets you killed evey single game. Hell, I've rarely seen it being used against me let alone every single game. Thing is, like Sprint, it fairly balanced and thought out when you go in depth. When you want to use the Spartan Charge you first have to build op momentum, then if you do manage to hit someone they still have the oppertunity to hit you back with lunge in the time it takes for you to recover from the blast. Recovery time that's fairly long might I add.
On the other end of things you should've not let them get so close. You can basicly do the same thing in Halo 4 when you melee out of Sprint, only in Halo 4 there's no recovery time for the one hit and this results into double melee's which were also a point of discussion back in the day. Point is, you let them get too close which costs you your head. Solution? Don't let them get close. Not remove a feature all together.
The Ground pound is in no way OP. It takes long to charge up, you basicly become a bright noisy target and the blast radius when you do make it downtown is minimal. The only way to land a kill is if you land right ontop of someone which should be hard for the one using ground pound should you see him and just thrust out of the way. If he does manage to one hit you than it's your own fault for not paying attention, should he bring your shields down then you have still got plenty of time to either run for cover or strike back.
-Here I fail to see how the Halo 2 and Halo 5 BR are different. Just because you move faster doesn't make the Halo 5 BR any better, if anything it should be easier to get out of dodge with the faster movement no? Double teaming someone in Halo 2 would also result in a '.5' killtime but with the added heavy bullet magnetism Halo 2 had.
All other loadout weapons have been balanced accordingly to prevent the BR from becoming the go to weapon again (like it was in Halo 2 and 4). In Halo 5 it serves a purpose as sort of an all porpose weapon easpecially powerful in medium range combat but with short and long range capabilities. The DMR (which is a 5 shot) fills the purpose of medium to long range and the AR is the go to weapon for short range combat. The Pistol will always lose to any of these weapons if you use the other weapons like you should. If not then you either have a skilled opponent with better aim than you, you just let him live too long and allowed him to kill you or he outplayed you and got the drop on you.
-I'm Onyx and still use the AR when people get too close, since you know... it takes people out faster than the Pistol up close. You should give it a try sometime.
Have you played the beta? 2 out of 3 weeks I believe had BR starts in Arena and it was horrible. No one dared to even move from their position since you'd get taken out by BR's. Eveyone just layed back and didn't engage. This is why we now have AR starts and i fully agree with this decision. If you still want your BR or other precision weapon, there are plenty spread across the map and the respawn times aren't that long.
-I fully agree with you on spawns. It's a pain. Though, fixing it isn't as easy as it appaers.
-The radar range has indeed been shortened in Arena (Not in BTB and Warzone) to make up for the relatively small maps. Else you'd see people pop up halfway across the map. I for one don't really mind this since it's easier to get the drop on people and takes away the kinda wall-hack like crutch, but I get that people want range increased. I wouldn't really mind either way.
-Radar still indicates people being on different height levels, I'm not sure how you didn't notice this.
-Zooming out when hit is for the better. This makes you able to at least keep an opponent from annihilating you with a (power)weapon without being able to have benn given the oppertunity to fight back. If you're getiing shot all the time, try to stick with cover.
-This was another eye-brow poker since the community was in absolute uproar about loadouts. There is nother that irritates competetive players more than randomness, and loadouts provided just that. You never knew what you were going up against when you knew someone was in a room or somewhere you were going which made it hard to play tactically and so forth.
In BTB you don't need a DMR to kill at range, the BR is perfectly fine for the type of batlles BTB provides. If you fail to kill at range, try to move in closer.
(On a side note I wonder why you call the AR a death machine here but enver use it in Arena)
-I agree that split-screen removal sucks, but if it were 30 fps with split-screen or 60 fps without I'd go for the latter everytime. Mainly because I rarely made use of split-screen but still, Its time has passed.
-There's also Warzone and Warzone assault for a grand total of 7 playists!
Yes, it's kind of a small amount. More scoial playlists would do the trick and that's coming.
-Again with the exaggeration. There's no way a friend of you aimed at a guys feet and scored a headshot. I find it harder to hit heads than Halo 2, but somehwat easier in comparison to Halo 3. Just depends on the person I guess.
-The maps are rather small with the idea of action packed combat. It's called Arena for a reason. But I do agree that somehwat larger maps wouldn't have hurt.
-The campaign was one of the better ones imo. Much more story and action packed gameplay. Was kinda disappointed by the way they depicted Locke before launch and how he turned out in the actual game. But overall it was a solid campaign, not the best, but definitly not the worst.
If you were the CEO of 343i I hope you'd learn that 343i doesn't just make calls on a whim. They've thought out everything they did and had to make some tough calls. I'd recommend watching the 'The Sprint' series on the Halo Channel or Youtube to see what I'm talking about.