Well yeah, different leagues could be nice. It's pretty much what I said with "Wushu 3min, Wushu 5min, Wushu 10min", except it would be like "Xmod 7rt, Xmod 15rt, Xmod 20~30rt"
Tho I don't see this as "league leveling", different leagues with different settings (rt) means different skills and different experiences. Nothing keeps people from enjoying playing in the 3 leagues because they enjoy each one of them in different ways.
All those leagues would be on the same level of "competitivity". There's no amount of competitivity, something is either suitable for competition, or is not.