In my experience Hell doesn't cw for like 90% of the day, only in the evenings. That leaves a huge window for everyone else who wants to cw in the meantime. The only thing in my opinion that player wars would actually solve, is going through the trouble of finding a teammate to cw with. I personally probably would use player wars during completely dead cw hours.
After all is said though, I feel that people who want to cw are already cwing and those who aren't cwing either aren't interested in it or just simply aren't good enough to compete even on the most basic level. To create a healthy and balanced ladder for player wars, sample of (let's be generous) 100 people wouldn't be enough regardless, since skill gaps would be far too wide.