I like to join a free public league in addition to my main league, but I'd love to see more options rather than just Public or Winners leagues. How about a same-level league option?
This way, Diamonds, Platinums, etc, can all enter into leagues with others of the same rating, which will not only make public leagues more competitive, but also offer a better insight to how we all measure up when not over or under-matched, as is often the case.
I'm a 3x Diamond, but I understand that many of my wins were barely deserving of a +1 in the W column. I would be eager to see how I would stack up in a Diamonds-only league. Yahoo would perhaps be wise to incentivize this as a pinnacle of success.