I think it would be really cool if we got all sorts of vehicles in Halo Infinite Forge. Like the civilian cars and trucks from Reach, the warthog troop transport variant etc. Having a lot of variation like that can really help you make up some funny and interesting gamemodes and maps, and they just overall add to the sandbox nature of the game, instead of only having the ‘balanced’ vehicles present.
Oh, and something similar to the Mammoth from Halo 3 and Halo 4, huge moving vehicles you can move around on are super neat