This is just a spur-of-the-moment thought I had this morning. What if there were Warzone variants that limited your REQ selection? My initial idea of “factions” was a Covie Warzone, or Forerunner Warzone, in which you could only use power weapons and vehicles of covenant or forerunner origin. (Loadouts are firmly UNSC right now of course, but I’d certainly not be against these modes removing loadouts and always spawning you with storm rifle or suppressor and side-arm equivalents)
This also presents a possibility of other interesting REQ restrictions. For example, what about a “Bronze Warzone” where you’re limited to the cards that bronze packs award. (Sort of a play on the “pauper deck” if you’re familiar with Magic The Gathering) Basically what I’m getting at is unique tactical thinking could come from forcing players to use a more limited tool set.