I just wanted to say I agree with you 100 hundred percent.
The main thing that has me upset about Reach and Halo 4 is the lack of notifiable skill in a player. Whenever my friends would try to argue halo vs cod my argument as a halo fanboy was always that in halo you did not simply run out and kill someone without a fight. In halo if you were in an evenly matched game every fight was a intense battle. If you wanted to be the one still standing you actually had to outsmart the other person. I honestly feel that you can no longer say that. Now halo is just like cod 90 percent of the time whoever gets the jump on the other person will win the fight. I'm sorry to burst the bubble 343 BUT THAT'S NOT HALO.
Halo is about like the OP said controlling the weapon and power up spawns, and controlling the map. Halo reach started the trend of ruining that by introducing armor abilities (this was the first step towards giving players a power with out them having to go out and fight for it.). Then halo 4 came out and you took that idea and ran with it. In halo 4 you first allowed people to pick there weapons (this is dumb because it encourages people to camp with things like dmr/boltshot. Why go get a shotgun when I can spawn with a boltshot that is just as good?). Then you introduced these completely dumb things called ordnance drops. I honestly can not put into words how disappointed I am to see halo with care packages. THIS GAME IS ABOUT WEAPON AND MAP CONTROL. That is what halo was founded on and what set it apart. Giving ordnance completely takes that out of the game. Take Vahalla for example. Say my team gets hill control, gets the laser, kills the other banshee right? Okay cool now I am free to wreck havok in my banshee because we had good weapon and map control and I was smart enough to keep it alive. But no I'm sorry DerpDerp on the other team got 2 kills and 3 assists so he now deserves to get a spartan laser ordnance that he can spawn safely in his base and kill my banshee. That is just dumb. Plain and simple.
Like the OP said you want to make a good halo multiplayer. Put in Halo 3, update the graphics, fix the minor bugs with the ranking system. Halo3 in my opinion was the peak that Halo should get to. You still had weapon and powerups that you had to go get. But they also added in pickups these are kinda armor abilities but they are one time use and you still have to compete for them they are not just handed out. Also the maps for halo3 were the best I have been very disappointed with the maps on reach and 4.
If nothing that I just said strikes home then let me offer you a proposal. You have two fan groups one crying out for the return of halo 2 and 3 gameplay. One who is satisfied with this new style. Why not do a remake of halo 2 like you did for halo ce. Accept this time bring back the whole halo 2 map list and instead of using 4's multiplayer use halo 2's. Then you will actually be making both sides happy and make more money. Because once halo 3's servers go down I know I'm done until there is change and I bet many more feel the same.