Just my opinion here based on some observations:
Win/Loss Ratio; although interesting, has become less relevant. The percentages mean less now because of so many strong players with toons on both sides, who switch on the fly depending on Guild needs, friend needs, time of day or just plain riding the streak. Riding the streak is for example, when you notice Imp side is consistently stronger over Pubs so you switch to your Imp toon to tip the percentages in your favor.
There is no faction loyalty anymore; just good players who play both sides depending on various factors. Because of this, when you're looking at win/loss %, you're beating and losing to the same people; think about it. What does the percentage really mean these days?