As the title says.
I think there’s already a discussion going on this.
EDIT
Yeah … here you go, now locked…
https://www.halowaypoint.com/en-us/forums/6e35355aecdf4fd0acdaee3cc4156fd4/topics/add-more-maps-to-quick-play/9cc4bd83-0555-468c-ae6a-f4c332e8419b/posts?page=1#post8
Quick playisn’t meant to include all maps. It’s meant to be a playlist for newer players to jump into and get used to playing Halo 5, only haveing a few maps is intentional too allo people to get used to controls, weapons and map movement. There are no plans from 343 to change this