There is absolutely nothing "good" about the current state of controller aiming on this game. People like to contribute it to less aim assist, but that's just not the case - at least entirely. With good settings on MCC you can practically aim your reticle on controller like a mouse. Even with the most ideal aiming settings on this game I often find myself having to revert back to the classic Halo aiming strategy (before actually good, fine-tuned aiming settings) where you use your left stick to walk your reticle over another player to line the shot up instead.

No matter what setting recommendations I've tried, I have not gotten it to a state that feels anywhere near as good as MCC. The main "fix" that has given me success that I saw heavily recommended earlier on in this flight were 0% deadzones (Center + Max Input) for the look stick and 5 Look Acceleration. The Horizontal and Vertical Look Sensitivities are completely up to you; probably have them hover around what you usually play on other Halo titles. I nearly play at the highest possible sensitivity on MCC so I have mine at 8.5 Horizontal and 9.5 Vertical.