Yes, I agree that the writer's voice is very important... and possibly the most important aspect of a piece of prose. I know I sometimes find myself not finishing an article about a subject I even like, simply because the voice of the writer seems absent, or even irritating, in some way.

If you want to get strict about it, you could say that there are no original ideas — everything we create is basically "re-cooked." As long as the writing is my own and I didn't set out to copy someone else's work, I consider it non-plagiarized.