Hardware is one of the most underrated parts of a home’s design in my opinion. It’s often overlooked and undervalued in both the attention we give it and the budget we allot for it. It’s something I did not give enough thought to when we remodeled our kitchen so I’m really glad that you’re putting thought into this!
I actually have a whole separate blog post on how to mix multiple metal finishes in a room and how to decide what colors look best together. You can read that here! But I’d love to share more on how to mix metals in an entire house.
Just as I recommend for individual rooms, limit yourself to 2-3 finishes for the entire house. Pick one color to be the dominant finish, the finish that you use on the majority of your pieces. Then use the second (and third if applicable) finish as an accent. And yes, I would recommend using the same finishes that you use in your bathroom and kitchen throughout the rest of your home.
If you have multiple finishes, incorporating them all in every room of your home, in one way or another, will create a cohesive look throughout the entire home. We want to avoid certain rooms having separate finishes from the rest of the house. Perhaps your bedrooms have brass overhead lights, black door knobs, and a few antique bronze frames hanging on the wall.
As for your question “Can I get too much of a finish in the home?” Incorporating multiple finishes throughout the house is the best way to avoid overdoing a finish. If the only metal color you use is brass and every element of hardware in your home is brass (from faucets, knobs, door handles, and overhead lights) then yes, it can be too much. But when you break up each one of those elements into 3 different finishes, suddenly it doesn’t look too overwhelming.
Hope this helps!