Hextech Crafting - Discouraging Diversity

So... I just played a Lulu game. Quite an excellent Lulu game even. I got an S rank on Lulu. Which is all fine and dandy, but I've already reached my allotment of chests for a while. But Lulu is still marked on my champion page as having earned a chest. The little chest is filled in. Which means I can't get a chest on her later. Basically what this means is that I'm encouraged to only play a small pool of champions that I've scored S with at all times except when I have a chest available. So, for a few games every six days, I'm encouraged to play new champs. Otherwise, diversity is crushed.

This really seems to be against the point of the new system.