Imagine playing as a UNSC Cadet who is kidnapped along with a few Marines/civilians/cadets during the final events of Halo 3 from Earth and escape only to be accidently teleported to an ancient world of the San 'Shyuum. There you encounter enslaved Covenant but mostly Sangheili–seeing as the Writ of Union had been voided.
Initially, your goal is to get back to Earth, but you’re seized by a group of ex-Covenant and forced to fight alongside them to avenge their fallen–with you watching the angered ex-Covenant kill the San ‘Shyuums’ people as well as devastate and take entire villages, but of course not without epic resistance from loyal Covenant, outnumbering San ‘Shyuum’ people, and other enslaved species with new weapons. Imagine using stealth to take down huge villages in an open-world action/adventure with Sangheili melee weapons and plasma shield. (Futuristic Ryse-type melee combat in first-person POV with SOME guns. Imagine fighting alongside the Arbiter at the end. Imagine being cavalry on alien-dragons raining down explosives. Since you’re a cadet, you build up your experience and learn new attacks and skills and build up your inventory. I want to be part of the dream factory that is 343i! It’s sort of like a Halo-Far Cry-type game.
What do you think?
I’m all for the idea of a halo open world survival game but you don’t need to have a complex plot you could just have a M.I.A marine trying to survive and get evac off the planet reach and it would still be a good game just as long as you don’t have to get malaria pills once every hour 
That sucked in Far Cry 2. Far Cry 3 though–freaking insane! The story could be whatever. I like what 343i did with Halo 4–expanding on the universe, but I don’t want to have to read the books since the games can only cover so much in a limited 10-chapter/8-hour single-player experience. By making a 25-50 hour game, they could create and attend to a whole lot of material, you know? And the experience to me is more like a television series. I freaking love Walter White in Breaking Bad–a lot of people do. You feel for the situations and the importance of the build-ups with longer material rather than in a short movie where you’re introduced to characters whose names won’t click after you’ve finished the movie. Oh well…Can’t wait to see what 343i does with their first “true” Halo game.
The only thing I liked about Far Cry 3 (and 2) was the map editor, but the terrible gameplay in both games kinda ruined the experience for me. Which is why Halo needs a proper map editor of its own! 
> That sucked in Far Cry 2. Far Cry 3 though–freaking insane! The story could be whatever. I like what 343i did with Halo 4–expanding on the universe, but I don’t want to have to read the books since the games can only cover so much in a limited 10-chapter/8-hour single-player experience. By making a 25-50 hour game, they could create and attend to a whole lot of material, you know? And the experience to me is more like a television series. I freaking love Walter White in Breaking Bad–a lot of people do. You feel for the situations and the importance of the build-ups with longer material rather than in a short movie where you’re introduced to characters whose names won’t click after you’ve finished the movie. Oh well…Can’t wait to see what 343i does with their first “true” Halo game.
You’d be surprised how much lore is in the books btw. Even just looking up the books in the halo wiki can give you a huge insight into the halo universe 
I think it’s best we keep open-world games with other franchises. I want 343i to stick to making Halo games. I explain why here
https://forums.halowaypoint.com/yaf_postst236788_Bringing-back-Halo--some-Suggestions.aspx
My only complaint with Far Cry was the limited field of view on the consoles. It gave me a headache every now and then. Other than that, the story was pretty sweet. Having to switch back to your map constantly was a pain, but not too bad. As for the map-editor, I can see 343i making a plethora of objects on an open-island–being able to spawn enemy NPC’s at a base on a completely blank island where you can create hills and dips Project Spark-style, spawn water, fog, set wind and dust into effect–spawn fire, trees, bushes, grass and rocks. I’d spend all day making the Palm Jumeirah island of Dubai.
I get you, but we both know 343i will move forward with their intentions. Create the best game possible. You can only do that by testing out what works and expand on it in ways that will push the industry forward. Halo: CE, Halo 2, Halo: 3–Bungie’s original ambition was fantastic for their time, for that era; however, now things are different. In this post, my thing was just expansion of the universe through a longer experience as a spinoff. Remember Halo: CE’s mission–Silent Cartographer–It’s arguably one of the best missions in Halo’s history, and I think it’s because you’re left to explore the whole island and debunk the mysteries. Halo: CE has the adventure-aspect I want to see in this open-world endeavor: just expanded upon–that’s all.