As an editor, I like to work closely with my writer. I like to know what they feel they need from me, especially with content editing. I love concise writing, and can usually cut works down to a better size. I am not afraid to say, "this is just a tangent, take it out..." or "does this really make sense right here? Shouldn't it be closer to the beginning of the piece?"
As a copy editor, I have a good command of grammar as well as AP style. I get rid of extra commas with delight.