They should definitely make something new with ODST because ODST are a HUGE part of Halo. Finding out that they were gone in
Halo 4 for what ever dumb reason was extremely dissapointing, but I guess it woud make since to not keep ODST on a ship practically made for Spartan IV's considering that ODSTs despise Spartans, but that's just campaign, I dont undseratnd why I cant wear ODST in multipplayer.
Halo 5: ODST
It would be extremely nice to have a separate ODST game to carry on the legacy of Buck's squad, but I doubt that's happening, so I suppose a better alternative would be to either have an ODST gametype for multiplayer or an "ODST Ops", or maybe both, which is also unlikely.
"ODST Operations" (If they're continuing Spartan Ops then this idea is a waste)
Considering that the UNSC have been working on an ODST SPI armor (basically cloaking for ODST if I remember correctly from
Halo Ghosts of Onyx) then I'm sure this would be incouperated. "ODST Ops" should probably take place during and interconnecting throughout the Halo 5 campaign or during the Chiefs absence. "ODST Ops" should include many stealth missions or orbital drops behind enemy lines because thats what we are made for, maybe even some reconnaissance missions (Hint hint, return of the target locater from Halo: Reach, Hint hint). Also, the scenary will probably be night time most of the time for stealth and so that you can use VISR affectively. But these missions should mainly focus on ODST drops because that would by a nice new little thing to see in Halo 5. And lastly, the silenced weaponry ODSTs use should actually benefit them.
New ODST Gametype
A new ODST gametype should include two simple beginning loadouts.
Loadout 1: Silenced SMG and Silenced Magnum with active camo and 2 frag grenades
Loadout 2: Silenced Assault Rifle (Maybe) and Silenced magnum with a bubble shield and 2 frag grenades
Also, in the beginning every match the player should spawn in a pod, 3 simultaneous beeps should sound, then off to the battlefield you go. Every time a player respawns they should respawn inside of a pod, but if the player is lucky enough to get an ordnance, they should have to wait to respawn in the pod to equip the weapon/armor enhancement of their choice. Also, these maps would need to be big, I'm talking half of forge world big. Another really nice thing to add to forge/the maps in general, would be weather/time of day change. (which is also unlikely). These new editions would revolutionize Halo and maybe, just maybe, give "Destiny" (Bungie's new game) a run for its money.