but that's really boring, and the benefit of having more ranked shop points is very appealing. Besides, there are a lot of other ways to get coupons, whereas there's only 1 way to get the ranked points.
5 Ranked battles a day would mean you get 5 coupons a day. Sure if you're gonna play a few thousand ranks battles then you make more coupons, but by then, im sure you wouldn't need them anymore. Game would probably die down too.