Opinionated lines, are only opinionated, in the mind of the person making the opinion. If that makes any sense. I understand lines that are not consensus or cloned, are possibly what you mean by opinionated. The trick is to find a book who's opinions, therefore there lines, are weak. Not very easy to do anymore. I much prefer to form my own opinion on what a line should be, if I come up with a significent difference between my line and my books line, I have a bet.
wil.