GEARS 5 (Why is so hard to give enemy chars a mode for them?)

I know vs uses enemies as playables but thats always been about the same in every gears game,now in judgement loucast came close with overun mode which was a good effort and in gow3 you had beast mode which was better but in gears 4&5 the swarm has gotten nothing for themselves to star them.With horde and escape for the cog,the gears are in good shape but how hard can it be to give the swarm somekind of mode where they are the main playable chars who have to do some kind of mission against the cog.