I kind of liked those missions in Halo 5 where you just walked around, talked to people, and collected intel.
However, they weren’t as fleshed out as they could have been. They need to be bigger and have more to do in them. I think they would be a great addition to campaign for some backstory.
For Halo 6, they could make the Infinity explorable, and let Chief roam around, talk to people for backstory, and even launch campaign missions from there.
Kind of like Mass Effect with the Normandy, or Splinter Cell: Blacklist.