While the 3rd person cam is necessary and vital for general and consistent gameplay, the 1st person cam is supposed to give a more immersion, but it's honestly so difficult to use and wonky that I never really use it. I think that a more dynamic and immersive alternative should be available.
Personally, I'd like to have an over the shoulder perspective, switching shoulders automatically and adjusting the camera's direction and zoom based on my target or how I'm moving if there is no target. Also, it should be able to handle targets behind your character or far above or below them without also losing sight of your character's head and torso.
I really think this could easily make combat far more dramatic, especially against larger enemies. Also, I've been trying my hand at a bit of roleplaying recently, and I think this could make conversations a bit more immersive.