Should you have the same metal finishes throughout your house?

I have antique brass lighting in my living room, dining room, and kitchen. It's a real open layout so it wouldn't have looked right to have different finishes. Now I'm decorating the bathroom and was leaning toward nickel lighting with matching towel bars, faucet, etc. The theme of the bathroom is a greenish botanical look. would it be okay to have nickel fixtures in the bathroom when I have antique brass everywhere else (my bedroom is aged bronze)?

Should you have the same metal finishes throughout your house?