Ok,so I have some ideas for gametypes with large player counts for halo xbox one (or whatever it’s going to be called. The first one is huge firefight games with tons of people on your side and tons of covenant. Not just dropships but the big ones as well. It would also be cool if around 15 minutes into the game you could board the ship, plant explaives and jump out before they blow the ship up and destroy it and that was the end of the game, but you only have one life and lots of enemies are on the ship so it creates a big risk vs reward aspect. Another idea is huge flood games where when you spawn as a flood you can pick your classes (Like the different types of flood from halo 3) and each one had pros and cons. It would be great to have the game start out with nobody as floods but hundreds of those tiny flood things to enter the map (which would be huge) and they keep coming back until they infect three people and those three people would be the alpha zombies (note that there would be still TONS of people alive) and all of the remaing small flood would scatter or infest the dead bodies of the three alpha zombies and that was the way the game would determine the alpha zombies. It would be awesome if these maps were in huge cities with vehicles (hornets) Also a new flying type flood class would be awesome or something like that which could go high up into the air to board air vehicles. Anyway, those were just a few of my suggestions, so post yours in the comment section and hopefully 343 will see this. 
These would be spectacular admissions for future Halos after the next. However, I don’t think 343i has had the time to make things this large scaled, but more so to focus on improving from Halo 4.
If the next gen can’t handle that, then the next gen isn’t good enough. These are some great ideas for future titles, but they probably are beyond 343i in their first major game on the new console. Halo 6 should have things like that, though.