League and My Achievement Whoring Problem

I am an achievement whore, and I think it would be cool if League had reward-type achievements. We got a start with the new icons you can unlock after five games as a given role in Team Builder. We got a couple more with the play-a-few-games and Perfect Ascension icons on Ascension gametype. I fully support these and hope we get more rewards like them in the future. Here are some of my ideas for how achievements could be implemented in standard LoL.

• After 300 kills/assists with a given champion, unlock that champ's icon as a summoner icon. (That seems like a lot, but I'm Bronze I and can usually get around 10 k/a in a match even if I'm sucking hard. If playing Braum or pre-rework Sona, I can get 20 easily.)
• After 1000 total kills/assists with that same champion (so, counting the 300 as part of the 1000), unlock silver border for that icon. After 2000, unlock gold border.
• After 1000/2000/4000 k/a with a jungler or support item equipped, unlock special jungler or support icon/add borders. (More kills required than for champion because this icon proves you know how to play a role, not a champ.)
• After maybe 600/1200/2400 k/a with a basic item that costs over 600g (1000g?), or a derivative item, unlock icon for that role (e.g. tank, mage, fighter, assassin). Less k/a required because you don't build Giant's Belt at the same time (early-mid game) you'd build Relic Shield (start of game).

The idea behind all of these is not so much to have a small challenge that influences playstyles (a criticism I've seen on a couple other threads), but to reward persistence and mastery of a champion or role. If I'm playing with a Braum icon--which I'm close to earning under this scheme, if I haven't already--both my teammates and my enemies know that I understand how to play him. If I'm playing with the reward for the support icon--which again, I'd probably have under this scheme--my teammates know I have their backs. If my duo queue partner is playing with a mage or Brand icon, the enemy knows to fear him.

What are your thoughts, community? What other achievements could be added? What could be done to improve my system, assuming it doesn't suck to begin with? Would you support the idea of achievements that reward mastery?