An issue with Hextech Crafting

So you are pumped about Hextech crafting! Ooooo what can I get! Let's play play play! Ok so I did my best and got my chests but what's this? I can't earn any more? Ok well... I guess that's fair because you need to pay the bills right but I am still pushing to get that S and the reward isn't there... I understand the limitations to the chests per week but my rating should have some influence on the chance that I get a key fragment regardless of my weekly hextech chest count. I just feel like there shouldn't be a limit to how much the player can be rewarded for performance. Other than that I am pretty grateful to finally get some cool skins for free Rito. I think something that can also be done is perhaps some kind of meter that fills up when you get an S beyond your weekly limits which influences the rarity of items you receive from your next hextech chest. Just a couple ideas.