@Riot: Are you really satisfied with how Thornmail works?
Passive damage reflect that requires no effort? Surely you can do better than that.
Once someone gets a Thornmail, you basically insta-lose when you attack them, even if you get magic resist and/or lifesteal. You're still smacking yourself up by attacking that target. Yes, it's got bad cost-efficiency, but it still has no fun factor attached to it when you're against it.
It might be there just to prevent 5-physical compositions, but it feels too binary as a result. Any plans regarding it, or is it "good spot, shut up"?