In Halo: Reach, you could set loadout weapons to “Random”, which would cause you to spawn in with a random weapon every time. I based a chaotic custom game mode around this, and my friends and I all loved it to death.
In Halo 4, they moved the option, putting it in General Traits or something like that, but the ability to have random weapons was still there, so I was still able to recreate the game mode.
In Halo 5, the only way to have random weapon spawns is to make the gametype Super Fiesta. This means that you can no longer have an Oddball, Grifball, Strongholds, KotH, etc. gametype with random weapons. (However, I know that Husky Raid is CTF with random weapons, but that was a developer gametype and cannot be replicated without a dev kit, afaik)
This is a severe issue in my opinion, and limits the “sandbox” that the developers have been toting around so lovingly. Who wants to see custom game random weapons back?
If you scroll further down the official 343 game modes in the Custom Games menu, they have a variety of fiesta game modes, such as Super Fiesta Assault, Super Fiesta Capture The Flag, and Super Fiesta Strongholds. Although I still do agree that the option to just have the weapons set to Random would be miles more convenient, as there still is no Fiesta Oddball. Having that convenience allows you to create any random game mode as you please.