You are new, so it's ok to express your feedback, even if it has before. the devs will be aware that any issues that keep coming up aren't from a small group repeating themselves, but is shared by even new players.
As for your idea. I think a DM would be good, but the other game types are too Overwatch-like. This is a story/scenario based game and all objectives are beautifully tied to a story with real meaning and relevance in a sequence of events. This is one of the many things that distinguish this game from others. Making KotK, CP, etc... would trivialize the immersion of this unique game and reduce the integrity of the lore. I left Overwatch because their missions objectives are meaningless and arbitrary. Why am I in Volkiya capturing this point? what is so important about this point? Why do the enemy team have to take the point? Why do the lose if they don't get it in time? Are their bombs strapped to their heads with timers? Will an omnic come and stomp them? Who is timing us? Why wouldn't they ignore the timer and keep trying to take this point? Why do they even want this piece of ground anyways? Why am I tracer fighting Mercy? Why is Doomfist working with Orisa? how are we even coming back to life over and over again? Why is Ana escorting a bomb to blow up a museum? It's all arbitrary. And that's fine. Overwatch is more of a competitive simulation with skins attached and hollow lore flavoring. And that's FINE, it's rated T, I'm not bagging on it.
But Raiders is rated M and typically appeals to adults. As such it has a more cohesive build than OW. Harec would NEVER fight against Shae. A Beherit doppelganger of Shae, sure, but not the REAL Shae. The missions have you doing actual sorry driven objectives, there's dialogue, events, etc... This would be more like Overwatch's Uprising and Retribution events, which I liked a lot (and when they stopped them I left).
HOWEVER! They could do CtF, KotH, etc... if it was done in a way that was more like a story driven mission against Beherit clones over NON arbitrary objectives. The closest in the game as an example is Fistful of Sand, which is kind of an escort payload mission in the form of an old man that can die. They would have to do something very similar as this in the form of a mission.
Just my opinion and two cents.