I went back to the game and played Exodus mission, where Noble 6 falls back on the planet and makes his way to New Alexandria. This mission is just PERFECT when in combat with marines. Joining in a civilian evac mission that is constantly going downhill, only for a random Spartan to come out of nowhere and completely turn the battle around. The marines not having any idea, care, or why you are there except being a literal angel dropping from the heavens.
What I feel this mission does best is that the ally AI just has so many dialogues. Either from the radio or when walking by them, they always got something to say that’s relevant. And when flying through the Falcon watching the battle, all you hear is every marine’s desperate help and each pleading for Noble 6’s aid. Seeing everyone’s depression when an evacuation shuttle of 600 falls into the sea, was so immersive and exciting.
Fans ask for a mission where you are just put in the middle of it all, and I believe that Exodus is the closest to a full-frontal battle as we can get where we get the sea the war away from the special ops missions. And especially when fighting alongside marines. There have to be more missions like these.