Don't know if you've noticed, but most FPS are looking out to be COD clones.
I get what you're saying, but I was impressed with their work and for a studios first game from scratch, they did an amazing job with Halo 4 and they're just getting started. I give them the benefit of the doubt.
I liked the custom loadouts to be honest, in Halo 4. I've never liked Bungie's past since Halo 2, in regards to the starting weapon being totally inferior. Halo CE did it right with the scoped pistol, it was a balanced starting weapon that allowed you to defend yourself from pretty much anything each time you spawned.
Bungie screwed that system up with Halo 2 and Halo 3, SMG starts and then assault rifle starts, so the entire two games revolved around dual wielding and then assault rifle starts. Start with trash, pick up better weapons, kill helpless peons spawning with trash to defend themselves with.
Halo 4 also introduced hit-scan, a very welcomed addition, no longer would you be depending on the host's connection to land your shots, instead when you fired the trigger, it was declared instant hit detection.
In Halo 5, I wouldn't mind the custom loadouts again, but as for the rest of the game, they need to ditch the armor abilities and go back to Halo 101, which is great maps designed to test the skill of players controlling/timing powerups (overshield and camo) and power weapons (snipers, rockets, shotgns, etc).